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TI-2026-33854 Aliases CVE-2026-46130GHSA-6hvc-rwfc-mp4j

dm-verity-fec: fix reading parity bytes split across blocks (take 3)

Priority LOW 30CWE-125Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · None · High
Fix status
Partial Red Hat: 2 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.

Summary

In the Linux kernel, the following vulnerability has been resolved: dm-verity-fec: fix reading parity bytes split across blocks (take 3) fec_decode_bufs() assumes that the parity bytes of the first RS codeword it decodes are never split across parity blocks. This assumption is false. Consider v->fec->block_size == 4096 && v->fec->roots == 17 && fio->nbufs == 1, for example. In that case, each call to fec_decode_bufs() consumes v->fec->roots * (fio->nbufs << DM_VERITY_FEC_BUF_RS_BITS) = 272 parity bytes. Considering that the parity data for each message block starts on a block boundary, the byte alignment in the parity data will iterate through 272*i mod 4096 until the 3 parity blocks have been consumed. On the 16th call (i=15), the alignment will be 4080 bytes into the first block. Only 16 bytes remain in that block, but 17 parity bytes will be needed. The code reads out-of-bounds from the parity block buffer. Fortunately this doesn't normally happen, since it can occur only for certain non-default values of fec_roots *and* when the maximum number of buffers couldn't be allocated due to low memory. For example with block_size=4096 only the following cases are affected: fec_roots=17: nbufs in [1, 3, 5, 15] fec_roots=19: nbufs in [1, 229] fec_roots=21: nbufs in [1, 3, 5, 13, 15, 39, 65, 195] fec_roots=23: nbufs in [1, 89] Regardless, fix it by refactoring how the parity blocks are read.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00126 2nd percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.6.160, 6.12.114, 6.2 +3Red Hat: 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.6.72 to before 6.6.160; 6.12.10 to before 6.12.114; 6.1.125 to before 6.26.6.160, 6.12.114, 6.2Patch availableCNA
LinuxLinux6.13 and later6.6.160, 6.12.114, 6.18.42, 7.0.7, 7.1Patch availableCNA
  • Linux VendorLinux Affected 6.6.72 to before 6.6.160; 6.12.10 to before 6.12.114; 6.1.125 to before 6.2 Fixed in 6.6.160, 6.12.114, 6.2 Patch available CNA
  • Linux VendorLinux Affected 6.13 and later Fixed in 6.6.160, 6.12.114, 6.18.42, 7.0.7, 7.1 Patch available CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*6.1.125 to before 6.2; 6.6.72 to before 6.7; 6.12.10 to before 6.13; 6.13.1 to before 7.0.7VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.13:-:*:*:*:*:*:*6.13VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.13:rc7:*:*:*:*:*:*6.13 rc7VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 6.1.125 to before 6.2; 6.6.72 to before 6.7; 6.12.10 to before 6.13; 6.13.1 to before 7.0.7 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.13:-:*:*:*:*:*:* Versions 6.13 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.13:rc7:*:*:*:*:*:* Versions 6.13 rc7 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.6.160, 6.12.114, 6.2
  • Fix · CNA Linux (Linux) Fixed in 6.6.160, 6.12.114, 6.18.42, 7.0.7, 7.1

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Not affected: 4 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-46130
  2. 2026-10-03 Alias added: GHSA-6hvc-rwfc-mp4j
  3. 2026-10-21 Fix available: Linux/Linux@03348b440f69417dc3a3c71d8271cff6b05f67fb, Linux/[email protected], Linux/[email protected] +1 · CNA
  4. 2026-10-21 2 new references · CNA
  5. 2026-10-29 Affected versions changed · Red Hat
  6. 2026-11-06 CISA SSVC decision points changed

References

Patch 2

Other 3

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences