TI-2026-77661 Aliases CVE-2026-92388 GHSA-r22r-3m6c-qv5r

Use after free in curl FTP wildcard listing write callback

HIGH 78CWE-416Published 2026-10-20 · Updated 2026-10-30

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: None · High · High
Fix status: Partial Red Hat: 1 fixed, 8 without a fix

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

Summary

Many curl releases from 7.21.0 through 8.22.0 are affected. A failed wildcard FTP LIST leaves the internal listing parser as the write callback, which causes a use-after-free (CWE-416) when the handle is reused, duplicated or freed. A remote attacker without privileges or user interaction can crash applications or write server response bytes into application memory.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

When an FTP wildcard `LIST` operation fails, libcurl omits the restoration path meant for successful listings, leaving the write callback set to the internal listing parser and the write callback data pointing directly to the easy handle. Subsequent reuse of this handle triggers an immediate crash, and cloning it via `curl_easy_duphandle()` copies this corrupted state into the duplicate. If the original handle is subsequently freed, executing a transfer on the cloned handle causes a heap use-after-free read against the dangling handle reference; alternatively, reusing the original or cloned handle while changing only `CURLOPT_WRITEDATA` (and omitting `CURLOPT_WRITEFUNCTION`) results in type confusion, forcing the internal parser to interpret incoming server response bytes into memory at the application-supplied write data pointer.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00699 53rd percentileScored 2026-11-07

Fix Partial Red Hat: 1 advisoryRed Hat: 1 fixed, 8 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: Yes
Technical impact: Partial

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
curl	curl	8.22.0 – 8.22.0; 8.21.0 – 8.21.0; 8.20.0 – 8.20.0; 8.19.0 – 8.19.0; 8.18.0 – 8.18.0; 8.17.0 – 8.17.0; 8.16.0 – 8.16.0; 8.15.0 – 8.15.0; 8.14.1 – 8.14.1; 8.14.0 – 8.14.0; 8.13.0 – 8.13.0; 8.12.1 – 8.12.1; 8.12.0 – 8.12.0; 8.11.1 – 8.11.1; 8.11.0 – 8.11.0; 8.10.1 – 8.10.1; 8.10.0 – 8.10.0; 8.9.1 – 8.9.1; 8.9.0 – 8.9.0; 8.8.0 – 8.8.0; 8.7.1 – 8.7.1; 8.7.0 – 8.7.0; 8.6.0 – 8.6.0; 8.5.0 – 8.5.0; 8.4.0 – 8.4.0; 8.3.0 – 8.3.0; 8.2.1 – 8.2.1; 8.2.0 – 8.2.0; 8.1.2 – 8.1.2; 8.1.1 – 8.1.1; 8.1.0 – 8.1.0; 8.0.1 – 8.0.1; 8.0.0 – 8.0.0; 7.88.1 – 7.88.1; 7.88.0 – 7.88.0; 7.87.0 – 7.87.0; 7.86.0 – 7.86.0; 7.85.0 – 7.85.0; 7.84.0 – 7.84.0; 7.83.1 – 7.83.1; 7.83.0 – 7.83.0; 7.82.0 – 7.82.0; 7.81.0 – 7.81.0; 7.80.0 – 7.80.0; 7.79.1 – 7.79.1; 7.79.0 – 7.79.0; 7.78.0 – 7.78.0; 7.77.0 – 7.77.0; 7.76.1 – 7.76.1; 7.76.0 – 7.76.0; 7.75.0 – 7.75.0; 7.74.0 – 7.74.0; 7.73.0 – 7.73.0; 7.72.0 – 7.72.0; 7.71.1 – 7.71.1; 7.71.0 – 7.71.0; 7.70.0 – 7.70.0; 7.69.1 – 7.69.1; 7.69.0 – 7.69.0; 7.68.0 – 7.68.0; 7.67.0 – 7.67.0; 7.66.0 – 7.66.0; 7.65.3 – 7.65.3; 7.65.2 – 7.65.2; 7.65.1 – 7.65.1; 7.65.0 – 7.65.0; 7.64.1 – 7.64.1; 7.64.0 – 7.64.0; 7.63.0 – 7.63.0; 7.62.0 – 7.62.0; 7.61.1 – 7.61.1; 7.61.0 – 7.61.0; 7.60.0 – 7.60.0; 7.59.0 – 7.59.0; 7.58.0 – 7.58.0; 7.57.0 – 7.57.0; 7.56.1 – 7.56.1; 7.56.0 – 7.56.0; 7.55.1 – 7.55.1; 7.55.0 – 7.55.0; 7.54.1 – 7.54.1; 7.54.0 – 7.54.0; 7.53.1 – 7.53.1; 7.53.0 – 7.53.0; 7.52.1 – 7.52.1; 7.52.0 – 7.52.0; 7.51.0 – 7.51.0; 7.50.3 – 7.50.3; 7.50.2 – 7.50.2; 7.50.1 – 7.50.1; 7.50.0 – 7.50.0; 7.49.1 – 7.49.1; 7.49.0 – 7.49.0; 7.48.0 – 7.48.0; 7.47.1 – 7.47.1; 7.47.0 – 7.47.0; 7.46.0 – 7.46.0; 7.45.0 – 7.45.0; 7.44.0 – 7.44.0; 7.43.0 – 7.43.0; 7.42.1 – 7.42.1; 7.42.0 – 7.42.0; 7.41.0 – 7.41.0; 7.40.0 – 7.40.0; 7.39.0 – 7.39.0; 7.38.0 – 7.38.0; 7.37.1 – 7.37.1; 7.37.0 – 7.37.0; 7.36.0 – 7.36.0; 7.35.0 – 7.35.0; 7.34.0 – 7.34.0; 7.33.0 – 7.33.0; 7.32.0 – 7.32.0; 7.31.0 – 7.31.0; 7.30.0 – 7.30.0; 7.29.0 – 7.29.0; 7.28.1 – 7.28.1; 7.28.0 – 7.28.0; 7.27.0 – 7.27.0; 7.26.0 – 7.26.0; 7.25.0 – 7.25.0; 7.24.0 – 7.24.0; 7.23.1 – 7.23.1; 7.23.0 – 7.23.0; 7.22.0 – 7.22.0; 7.21.7 – 7.21.7; 7.21.6 – 7.21.6; 7.21.5 – 7.21.5; 7.21.4 – 7.21.4; 7.21.3 – 7.21.3; 7.21.2 – 7.21.2; 7.21.1 – 7.21.1; 7.21.0 – 7.21.0	—	No fix listed	CNA

curl Vendorcurl Affected 8.22.0 – 8.22.0; 8.21.0 – 8.21.0; 8.20.0 – 8.20.0; 8.19.0 – 8.19.0; 8.18.0 – 8.18.0; 8.17.0 – 8.17.0; 8.16.0 – 8.16.0; 8.15.0 – 8.15.0; 8.14.1 – 8.14.1; 8.14.0 – 8.14.0; 8.13.0 – 8.13.0; 8.12.1 – 8.12.1; 8.12.0 – 8.12.0; 8.11.1 – 8.11.1; 8.11.0 – 8.11.0; 8.10.1 – 8.10.1; 8.10.0 – 8.10.0; 8.9.1 – 8.9.1; 8.9.0 – 8.9.0; 8.8.0 – 8.8.0; 8.7.1 – 8.7.1; 8.7.0 – 8.7.0; 8.6.0 – 8.6.0; 8.5.0 – 8.5.0; 8.4.0 – 8.4.0; 8.3.0 – 8.3.0; 8.2.1 – 8.2.1; 8.2.0 – 8.2.0; 8.1.2 – 8.1.2; 8.1.1 – 8.1.1; 8.1.0 – 8.1.0; 8.0.1 – 8.0.1; 8.0.0 – 8.0.0; 7.88.1 – 7.88.1; 7.88.0 – 7.88.0; 7.87.0 – 7.87.0; 7.86.0 – 7.86.0; 7.85.0 – 7.85.0; 7.84.0 – 7.84.0; 7.83.1 – 7.83.1; 7.83.0 – 7.83.0; 7.82.0 – 7.82.0; 7.81.0 – 7.81.0; 7.80.0 – 7.80.0; 7.79.1 – 7.79.1; 7.79.0 – 7.79.0; 7.78.0 – 7.78.0; 7.77.0 – 7.77.0; 7.76.1 – 7.76.1; 7.76.0 – 7.76.0; 7.75.0 – 7.75.0; 7.74.0 – 7.74.0; 7.73.0 – 7.73.0; 7.72.0 – 7.72.0; 7.71.1 – 7.71.1; 7.71.0 – 7.71.0; 7.70.0 – 7.70.0; 7.69.1 – 7.69.1; 7.69.0 – 7.69.0; 7.68.0 – 7.68.0; 7.67.0 – 7.67.0; 7.66.0 – 7.66.0; 7.65.3 – 7.65.3; 7.65.2 – 7.65.2; 7.65.1 – 7.65.1; 7.65.0 – 7.65.0; 7.64.1 – 7.64.1; 7.64.0 – 7.64.0; 7.63.0 – 7.63.0; 7.62.0 – 7.62.0; 7.61.1 – 7.61.1; 7.61.0 – 7.61.0; 7.60.0 – 7.60.0; 7.59.0 – 7.59.0; 7.58.0 – 7.58.0; 7.57.0 – 7.57.0; 7.56.1 – 7.56.1; 7.56.0 – 7.56.0; 7.55.1 – 7.55.1; 7.55.0 – 7.55.0; 7.54.1 – 7.54.1; 7.54.0 – 7.54.0; 7.53.1 – 7.53.1; 7.53.0 – 7.53.0; 7.52.1 – 7.52.1; 7.52.0 – 7.52.0; 7.51.0 – 7.51.0; 7.50.3 – 7.50.3; 7.50.2 – 7.50.2; 7.50.1 – 7.50.1; 7.50.0 – 7.50.0; 7.49.1 – 7.49.1; 7.49.0 – 7.49.0; 7.48.0 – 7.48.0; 7.47.1 – 7.47.1; 7.47.0 – 7.47.0; 7.46.0 – 7.46.0; 7.45.0 – 7.45.0; 7.44.0 – 7.44.0; 7.43.0 – 7.43.0; 7.42.1 – 7.42.1; 7.42.0 – 7.42.0; 7.41.0 – 7.41.0; 7.40.0 – 7.40.0; 7.39.0 – 7.39.0; 7.38.0 – 7.38.0; 7.37.1 – 7.37.1; 7.37.0 – 7.37.0; 7.36.0 – 7.36.0; 7.35.0 – 7.35.0; 7.34.0 – 7.34.0; 7.33.0 – 7.33.0; 7.32.0 – 7.32.0; 7.31.0 – 7.31.0; 7.30.0 – 7.30.0; 7.29.0 – 7.29.0; 7.28.1 – 7.28.1; 7.28.0 – 7.28.0; 7.27.0 – 7.27.0; 7.26.0 – 7.26.0; 7.25.0 – 7.25.0; 7.24.0 – 7.24.0; 7.23.1 – 7.23.1; 7.23.0 – 7.23.0; 7.22.0 – 7.22.0; 7.21.7 – 7.21.7; 7.21.6 – 7.21.6; 7.21.5 – 7.21.5; 7.21.4 – 7.21.4; 7.21.3 – 7.21.3; 7.21.2 – 7.21.2; 7.21.1 – 7.21.1; 7.21.0 – 7.21.0 Fixed in — No fix listed CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPE	Versions	Role	Vendor
cpe:2.3:a:haxx:curl::::::::	—	—	Haxx

cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:* Versions — — ·Haxx

Remediation

The sources list no fixed version for curl. Red Hat fixes Red Hat Hardened Images in RHSA-2026:82895, and Red Hat has no fix available for Red Hat Enterprise Linux 7, 8, 9 and 10, Red Hat JBoss Core Services and Red Hat Satellite 6.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Red Hat 1 advisory

RHSA-2026:82895 Released 2026-10-14 · Red Hat rating Important
Red Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images curl-8.23.0-0.1.hum1@aarch64, curl-8.23.0-0.1.hum1@s390x, curl-8.23.0-0.1.hum1@src +10

Vendor assessments

Red Hat

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

Product	Status	Plan or fix
Red Hat Enterprise Linux 10	Affected	No fix yet
Red Hat Enterprise Linux 7	Affected	No fix yet: Fix deferred
Red Hat Enterprise Linux 8	Affected	No fix yet: Fix deferred
Red Hat Enterprise Linux 9	Affected	No fix yet
Red Hat Hardened Images	Affected	No fix yet
Red Hat JBoss Core Services	Affected	No fix yet: Fix deferred
Red Hat OpenShift AI (RHOAI)	Affected	—
Red Hat Satellite 6	Affected	No fix yet: Fix deferred
Red Hat Hardened Images	Fixed	RHSA-2026:82895

Not affected: 7 products

Confidential Compute Attestation
Red Hat Enterprise Linux 10
Red Hat Enterprise Linux 6
Red Hat Enterprise Linux 8
Red Hat Enterprise Linux 9
Red Hat OpenShift AI (RHOAI)
Red Hat Satellite 6

Timeline

2026-10-21 Threatist record created from CVE-2026-92388
2026-10-21 Alias added: GHSA-r22r-3m6c-qv5r
2026-10-30 CVSS score added · CISA ADP
2026-10-30 Weakness changed · CISA ADP
2026-10-30 CISA SSVC decision points changed
2026-10-30 Priority changed: LOW → HIGH
2026-10-31 EPSS moved to the 50th–90th percentile
2026-11-06 Affected versions changed · Red Hat

References

Other 3

TI-2023-19922 Out-of-bounds write in curl CVSS 3.1CRITICAL 9.8
TI-2026-16162 Negotiate ambient user conn reuse CVSS 3.1CRITICAL 9.8
TI-2026-10231 cross-origin Digest auth state leak CVSS 3.1CRITICAL 9.8
TI-2026-09063 HTTP/2 stream-dependency tree UAF CVSS 3.1CRITICAL 9.8
TI-2026-07976 stale proxy password leak CVSS 3.1CRITICAL 9.8
TI-2026-07845 SASL double-free CVSS 3.1CRITICAL 9.8

See all 103 →

Sources

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