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TI-2026-79459 Aliases CVE-2026-115374GHSA-m6pj-594x-rw4f

Signature bypass in Incus S3 presigned uploads exposes other objects

Priority LOW 30CWE-347Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Security bypass
Confidentiality · integrity · availability
High · Low · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-347.

Summary

Incus from 7.0.0 before 7.0.2 and from 7.1.0 before 7.5.0 contains a signature verification flaw in its built-in S3 server (CWE-347). Holders of a presigned upload URL can inject unsigned x-amz-* headers into their requests. An attacker with such a URL can add an unsigned X-Amz-Copy-Source header to copy other bucket objects onto the granted key, disclosing their contents and ETags.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

Incus 7.0.0 before 7.0.2 and 7.1.0 before 7.5.0 contains a signature verification flaw in its built-in S3 server that allows presigned URL holders to inject unsigned x-amz-* headers. Attackers can add an unsigned X-Amz-Copy-Source header to a presigned upload URL to copy other bucket objects onto the granted key, disclosing their contents and ETags.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00183 7th percentileScored 2026-11-07
Fix Fixed incus (lxc): 7.0.2, 7.5.0

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
lxcincus7.0.0 to before 7.0.2; 7.1.0 to before 7.5.07.0.2, 7.5.0Patch availableCNA
  • incus Vendorlxc Affected 7.0.0 to before 7.0.2; 7.1.0 to before 7.5.0 Fixed in 7.0.2, 7.5.0 Patch available CNA

CPE names Threatist (inferred) · 1

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

CPEVersionsRoleVendor
cpe:2.3:a:linuxcontainers:incus:*:*:*:*:*:*:*:*——lxc
  • cpe:2.3:a:linuxcontainers:incus:*:*:*:*:*:*:*:* Versions — — ·lxc

Remediation

The fixed versions are Incus 7.0.2 and Incus 7.5.0.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA incus (lxc) Fixed in 7.0.2, 7.5.0

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    lxc incus 7.0.2, 7.5.0

    3 records Highest priority Priority MEDIUM 1 MEDIUM, 2 LOW

    Other records, highest priority first

    • TI-2026-79460 Path traversal in Incus lets clients write files on the hostPriority MEDIUM 43
    • TI-2026-79461 Incus lets restricted clients copy volumes from other projectsPriority LOW 36
    Show all 3 records →

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-22 Threatist record created from CVE-2026-115374
  2. 2026-10-22 Alias added: GHSA-m6pj-594x-rw4f
  3. 2026-10-23 Priority changed: MEDIUM → LOW
  4. 2026-10-23 CISA SSVC decision points changed
  5. 2026-10-24 Affected versions changed · Red Hat
  6. 2026-10-24 CVSS score added · Red Hat

References

Advisory 1

  • TI-2019-04061 runc through 1.0-rc6, as used in Docker before 18.09.2 and other products, allows… CVSS 3.1HIGH 8.6
  • TI-2026-45063 Incus vulnerable to root RCE via image backup.yaml symlink CVSS 3.1CRITICAL 9.9
  • TI-2026-44978 Incus: Cross-project instance copy bypasses target project restrictions via TOCTOU in config merge CVSS 3.1CRITICAL 9.9
  • TI-2026-36039 Incus has an arbitrary file write on its client due to trusted image hash CVSS 3.1CRITICAL 9.9
  • TI-2026-36024 Incus has an arbitrary file write via path traversal in S3 multipart upload CVSS 3.1CRITICAL 9.9
  • TI-2026-36022 Incus has a restricted project bypass leading to arbitrary command execution CVSS 3.1CRITICAL 9.9
See all 63 →

Sources

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