crypto: pcrypt - Fix handling of MAY_BACKLOG requests
Priority MEDIUM 50CWE-390Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 38 fixed, 2 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.
Summary
In the Linux kernel, the following vulnerability has been resolved: crypto: pcrypt - Fix handling of MAY_BACKLOG requests MAY_BACKLOG requests can return EBUSY. Handle them by checking for that value and filtering out EINPROGRESS notifications.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00681 52nd percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.10.258, 5.15.209, 6.1.175 +5Red Hat: 12 advisoriesRed Hat: 38 fixed, 2 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 2.6.34 and later | 5.10.258, 5.15.209, 6.1.175, 6.6.140, 6.12.86, 6.18.27, 7.0.4, 7.1 | Patch available | CNA |
- Linux VendorLinux Affected 2.6.34 and later Fixed in 5.10.258, 5.15.209, 6.1.175, 6.6.140, 6.12.86, 6.18.27, 7.0.4, 7.1 Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 2.6.34 to before 5.10.258; 5.11 to before 5.15.209; 5.16 to before 6.1.175; 6.2 to before 6.6.140; 6.7 to before 6.12.86; 6.13 to before 6.18.27; 6.19 to before 7.0.4 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 2.6.34 to before 5.10.258; 5.11 to before 5.15.209; 5.16 to before 6.1.175; 6.2 to before 6.6.140; 6.7 to before 6.12.86; 6.13 to before 6.18.27; 6.19 to before 7.0.4 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.10.258, 5.15.209, 6.1.175, 6.6.140, 6.12.86, 6.18.27, 7.0.4, 7.1
Red Hat 12 advisories
- RHSA-2026:93047 Released 2026-10-30 · Red Hat rating Importantkernel-rt security, bug fix, and enhancement update
- Red Hat Enterprise Linux Real Time E4S (v.9.2) kernel-rt-5.14.0-284.200.1.rt14.485.el9_2, kernel-rt-core-5.14.0-284.200.1.rt14.485.el9_2, kernel-rt-debug-5.14.0-284.200.1.rt14.485.el9_2 +9
- Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2) kernel-rt-5.14.0-284.200.1.rt14.485.el9_2, kernel-rt-core-5.14.0-284.200.1.rt14.485.el9_2, kernel-rt-debug-5.14.0-284.200.1.rt14.485.el9_2 +11
- RHSA-2026:92997 Released 2026-10-30 · Red Hat rating Importantkernel security update
- Red Hat Enterprise Linux BaseOS E4S (v.8.8) bpftool-4.18.0-477.177.1.el8_8, kernel-4.18.0-477.177.1.el8_8, kernel-abi-stablelists-4.18.0-477.177.1.el8_8 +14
- Red Hat Enterprise Linux BaseOS TUS (v.8.8) bpftool-4.18.0-477.177.1.el8_8, kernel-4.18.0-477.177.1.el8_8, kernel-abi-stablelists-4.18.0-477.177.1.el8_8 +14
- RHSA-2026:92993 Released 2026-10-30 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream E4S (v.9.2) kernel-64k-debug-devel-5.14.0-284.200.1.el9_2, kernel-64k-debug-devel-matched-5.14.0-284.200.1.el9_2, kernel-64k-devel-5.14.0-284.200.1.el9_2 +10
- Red Hat Enterprise Linux BaseOS E4S (v.9.2) bpftool-7.0.0-284.200.1.el9_2, kernel-5.14.0-284.200.1.el9_2, kernel-64k-5.14.0-284.200.1.el9_2 +29
Show 9 more Red Hat advisories
- RHSA-2026:91585 Released 2026-10-28 · Red Hat rating Importantkernel security update
- Red Hat Enterprise Linux BaseOS AUS (v.8.4) bpftool-4.18.0-305.216.1.el8_4, kernel-4.18.0-305.216.1.el8_4, kernel-abi-stablelists-4.18.0-305.216.1.el8_4 +14
- Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.4) bpftool-4.18.0-305.216.1.el8_4, kernel-4.18.0-305.216.1.el8_4, kernel-abi-stablelists-4.18.0-305.216.1.el8_4 +14
- RHSA-2026:91489 Released 2026-10-28 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream E4S (v.9.4) kernel-64k-debug-devel-5.14.0-427.158.1.el9_4, kernel-64k-debug-devel-matched-5.14.0-427.158.1.el9_4, kernel-64k-devel-5.14.0-427.158.1.el9_4 +11
- Red Hat Enterprise Linux BaseOS E4S (v.9.4) bpftool-7.3.0-427.158.1.el9_4, kernel-5.14.0-427.158.1.el9_4, kernel-64k-5.14.0-427.158.1.el9_4 +29
- Red Hat Enterprise Linux Real Time E4S (v.9.4) kernel-rt-5.14.0-427.158.1.el9_4, kernel-rt-core-5.14.0-427.158.1.el9_4, kernel-rt-debug-5.14.0-427.158.1.el9_4 +9
- Red Hat Enterprise Linux Real Time for NFV E4S (v.9.4) kernel-rt-5.14.0-427.158.1.el9_4, kernel-rt-core-5.14.0-427.158.1.el9_4, kernel-rt-debug-5.14.0-427.158.1.el9_4 +11
- RHSA-2026:85000 Released 2026-10-19 · Red Hat rating Importantkernel security update
- Red Hat Enterprise Linux BaseOS AUS (v.8.6) bpftool-4.18.0-372.223.1.el8_6, kernel-4.18.0-372.223.1.el8_6, kernel-abi-stablelists-4.18.0-372.223.1.el8_6 +14
- Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.6) bpftool-4.18.0-372.223.1.el8_6, kernel-4.18.0-372.223.1.el8_6, kernel-abi-stablelists-4.18.0-372.223.1.el8_6 +14
- RHSA-2026:75560 Released 2026-10-05 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream EUS (v. 10.0) kernel-64k-debug-devel-6.12.0-55.108.1.el10_0, kernel-64k-debug-devel-matched-6.12.0-55.108.1.el10_0, kernel-64k-devel-6.12.0-55.108.1.el10_0 +12
- Red Hat Enterprise Linux BaseOS EUS (v. 10.0) kernel-6.12.0-55.108.1.el10_0, kernel-64k-6.12.0-55.108.1.el10_0, kernel-64k-core-6.12.0-55.108.1.el10_0 +28
- Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) kernel-tools-libs-devel-6.12.0-55.108.1.el10_0, libperf-6.12.0-55.108.1.el10_0
- Red Hat Enterprise Linux Real Time EUS (v. 10.0) kernel-rt-6.12.0-55.108.1.el10_0, kernel-rt-64k-6.12.0-55.108.1.el10_0, kernel-rt-64k-core-6.12.0-55.108.1.el10_0 +21
- Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0) kernel-rt-6.12.0-55.108.1.el10_0, kernel-rt-core-6.12.0-55.108.1.el10_0, kernel-rt-debug-6.12.0-55.108.1.el10_0 +11
- RHSA-2026:74174 Released 2026-10-01 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat CodeReady Linux Builder EUS (v.9.6) kernel-tools-libs-devel-5.14.0-570.146.1.el9_6, libperf-5.14.0-570.146.1.el9_6
- Red Hat Enterprise Linux AppStream EUS (v.9.6) kernel-64k-debug-devel-5.14.0-570.146.1.el9_6, kernel-64k-debug-devel-matched-5.14.0-570.146.1.el9_6, kernel-64k-devel-5.14.0-570.146.1.el9_6 +12
- Red Hat Enterprise Linux BaseOS EUS (v.9.6) kernel-5.14.0-570.146.1.el9_6, kernel-64k-5.14.0-570.146.1.el9_6, kernel-64k-core-5.14.0-570.146.1.el9_6 +28
- Red Hat Enterprise Linux Real Time EUS (v.9.6) kernel-rt-5.14.0-570.146.1.el9_6, kernel-rt-64k-5.14.0-570.146.1.el9_6, kernel-rt-64k-core-5.14.0-570.146.1.el9_6 +21
- Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6) kernel-rt-5.14.0-570.146.1.el9_6, kernel-rt-core-5.14.0-570.146.1.el9_6, kernel-rt-debug-5.14.0-570.146.1.el9_6 +11
- RHSA-2026:66180 Released 2026-09-10 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-687.46.1.el9_8, kernel-64k-debug-devel-matched-5.14.0-687.46.1.el9_8, kernel-64k-devel-5.14.0-687.46.1.el9_8 +12
- Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-687.46.1.el9_8, kernel-64k-5.14.0-687.46.1.el9_8, kernel-64k-core-5.14.0-687.46.1.el9_8 +28
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-687.46.1.el9_8, libperf-5.14.0-687.46.1.el9_8
- Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-687.46.1.el9_8, kernel-rt-64k-5.14.0-687.46.1.el9_8, kernel-rt-64k-core-5.14.0-687.46.1.el9_8 +21
- Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-687.46.1.el9_8, kernel-rt-core-5.14.0-687.46.1.el9_8, kernel-rt-debug-5.14.0-687.46.1.el9_8 +9
- RHSA-2026:66000 Released 2026-09-09 · Red Hat rating Importantkernel security update
- Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-553.160.1.el8_10, kernel-4.18.0-553.160.1.el8_10, kernel-abi-stablelists-4.18.0-553.160.1.el8_10 +19
- Red Hat Enterprise Linux CRB (v. 8) kernel-tools-libs-devel-4.18.0-553.160.1.el8_10
- RHSA-2026:64770 Released 2026-09-08 · Red Hat rating Importantkernel-rt security update
- Red Hat Enterprise Linux NFV (v. 8) kernel-rt-4.18.0-553.160.1.rt7.501.el8_10, kernel-rt-core-4.18.0-553.160.1.rt7.501.el8_10, kernel-rt-debug-4.18.0-553.160.1.rt7.501.el8_10 +9
- Red Hat Enterprise Linux RT (v. 8) kernel-rt-4.18.0-553.160.1.rt7.501.el8_10, kernel-rt-core-4.18.0-553.160.1.rt7.501.el8_10, kernel-rt-debug-4.18.0-553.160.1.rt7.501.el8_10 +7
- RHSA-2026:57251 Released 2026-08-20 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.49.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.49.1.el10_2, kernel-64k-devel-6.12.0-211.49.1.el10_2 +12
- Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.49.1.el10_2, kernel-64k-6.12.0-211.49.1.el10_2, kernel-64k-core-6.12.0-211.49.1.el10_2 +29
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.49.1.el10_2, libperf-6.12.0-211.49.1.el10_2
- Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.49.1.el10_2, kernel-rt-64k-6.12.0-211.49.1.el10_2, kernel-rt-64k-core-6.12.0-211.49.1.el10_2 +21
- Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.49.1.el10_2, kernel-rt-core-6.12.0-211.49.1.el10_2, kernel-rt-debug-6.12.0-211.49.1.el10_2 +9
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 7 | Affected | No fix yet |
| Red Hat Enterprise Linux 9 | Affected | No fix yet |
| Red Hat CodeReady Linux Builder EUS (v.9.6) | Fixed | RHSA-2026:74174 |
| Red Hat Enterprise Linux AppStream (v. 10) | Fixed | RHSA-2026:57251 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2026:66180 |
| Red Hat Enterprise Linux AppStream E4S (v.9.2) | Fixed | RHSA-2026:92993 |
| Red Hat Enterprise Linux AppStream E4S (v.9.4) | Fixed | RHSA-2026:91489 |
| Red Hat Enterprise Linux AppStream EUS (v. 10.0) | Fixed | RHSA-2026:75560 |
| Red Hat Enterprise Linux AppStream EUS (v.9.6) | Fixed | RHSA-2026:74174 |
| Red Hat Enterprise Linux BaseOS (v. 10) | Fixed | RHSA-2026:57251 |
| Red Hat Enterprise Linux BaseOS (v. 8) | Fixed | RHSA-2026:66000 |
| Red Hat Enterprise Linux BaseOS (v. 9) | Fixed | RHSA-2026:66180 |
| Red Hat Enterprise Linux BaseOS AUS (v.8.4) | Fixed | RHSA-2026:91585 |
| Red Hat Enterprise Linux BaseOS AUS (v.8.6) | Fixed | RHSA-2026:85000 |
| Red Hat Enterprise Linux BaseOS E4S (v.8.8) | Fixed | RHSA-2026:92997 |
| Red Hat Enterprise Linux BaseOS E4S (v.9.2) | Fixed | RHSA-2026:92993 |
| Red Hat Enterprise Linux BaseOS E4S (v.9.4) | Fixed | RHSA-2026:91489 |
| Red Hat Enterprise Linux BaseOS EUS (v. 10.0) | Fixed | RHSA-2026:75560 |
| Red Hat Enterprise Linux BaseOS EUS (v.9.6) | Fixed | RHSA-2026:74174 |
| Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.4) | Fixed | RHSA-2026:91585 |
| Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.6) | Fixed | RHSA-2026:85000 |
| Red Hat Enterprise Linux BaseOS TUS (v.8.8) | Fixed | RHSA-2026:92997 |
| Red Hat Enterprise Linux CRB (v. 8) | Fixed | RHSA-2026:66000 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) | Fixed | RHSA-2026:57251 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) | Fixed | RHSA-2026:66180 |
| Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) | Fixed | RHSA-2026:75560 |
| Red Hat Enterprise Linux NFV (v. 8) | Fixed | RHSA-2026:64770 |
| Red Hat Enterprise Linux RT (v. 8) | Fixed | RHSA-2026:64770 |
| Red Hat Enterprise Linux Real Time (v. 10) | Fixed | RHSA-2026:57251 |
| Red Hat Enterprise Linux Real Time (v. 9) | Fixed | RHSA-2026:66180 |
| Red Hat Enterprise Linux Real Time E4S (v.9.2) | Fixed | RHSA-2026:93047 |
| Red Hat Enterprise Linux Real Time E4S (v.9.4) | Fixed | RHSA-2026:91489 |
| Red Hat Enterprise Linux Real Time EUS (v. 10.0) | Fixed | RHSA-2026:75560 |
| Red Hat Enterprise Linux Real Time EUS (v.9.6) | Fixed | RHSA-2026:74174 |
| Red Hat Enterprise Linux Real Time for NFV (v. 10) | Fixed | RHSA-2026:57251 |
| Red Hat Enterprise Linux Real Time for NFV (v. 9) | Fixed | RHSA-2026:66180 |
| Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2) | Fixed | RHSA-2026:93047 |
| Red Hat Enterprise Linux Real Time for NFV E4S (v.9.4) | Fixed | RHSA-2026:91489 |
| Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0) | Fixed | RHSA-2026:75560 |
| Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6) | Fixed | RHSA-2026:74174 |
Not affected: 1 product
- Red Hat Enterprise Linux 6
Timeline
- 2026-10-02 Threatist record created from CVE-2026-43493
- 2026-10-03 Alias added: GHSA-v9g7-8cgp-9v29
- 2026-10-05 Fix available: RHSA-2026:75560 · Red Hat
- 2026-10-05 Fix available: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux BaseOS EUS (v. 10.0), Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) +2 · Red Hat
- 2026-10-16 CISA SSVC decision points changed
- 2026-10-19 Weakness changed · CISA ADP
- 2026-10-20 Fix available: RHSA-2026:85000 · Red Hat
- 2026-10-20 Fix available: Red Hat Enterprise Linux BaseOS AUS (v.8.6), Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.6) · Red Hat
- 2026-10-25 EPSS moved to the 50th–90th percentile
- 2026-10-29 Fix available: RHSA-2026:91585 · Red Hat
- 2026-10-29 Fix available: RHSA-2026:91489 · Red Hat
- 2026-10-30 Fix available: Red Hat Enterprise Linux AppStream E4S (v.9.4), Red Hat Enterprise Linux BaseOS AUS (v.8.4), Red Hat Enterprise Linux BaseOS E4S (v.9.4) +3 · Red Hat
- 2026-10-30 Fix available: RHSA-2026:93047 · Red Hat
- 2026-10-30 Fix available: Red Hat Enterprise Linux AppStream E4S (v.9.2), Red Hat Enterprise Linux BaseOS E4S (v.8.8), Red Hat Enterprise Linux BaseOS E4S (v.9.2) +3 · Red Hat
- 2026-10-31 Fix available: RHSA-2026:92993 · Red Hat
- 2026-10-31 Fix available: RHSA-2026:92997 · Red Hat
References
Patch 8
- https://git.kernel.org/stable/c/ae7e95638d956d556d74b9abb9e780d3bd3dcd9e
- https://git.kernel.org/stable/c/1d7f07df450bac3301938fbc4251f2611be4084e
- https://git.kernel.org/stable/c/76641449b28979ebd6c02e9598367e119e385236
- https://git.kernel.org/stable/c/9f1cbca178c03188e201ed175251372149bb25f2
- https://git.kernel.org/stable/c/eb34e243df57e32f4c08fa191f3602ea19076276
- https://git.kernel.org/stable/c/77d55bc8675ee851ed639dc9be77325a8024cf67
- https://git.kernel.org/stable/c/46271895ddfb1ba41f89f7e0dffbe9c2bcf7380a
- https://git.kernel.org/stable/c/915b692e6cb723aac658c25eb82c58fd81235110
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Sources
- CVE-2026-43493 · CVE Program
- CVE-2026-43493 · NVD
- FIRST EPSS
- GHSA-v9g7-8cgp-9v29 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-43493 · Red Hat security data · CC BY 4.0
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