CVE-2026-115374
Incus 7.0.0 before 7.0.2 and 7.1.0 before 7.5.0 Unsigned Header Bypass in Presigned S3 Upload URLs
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Incus 7.0.0 before 7.0.2 and 7.1.0 before 7.5.0 Unsigned Header Bypass in Presigned S3 Upload URLs
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.
- Record
CVE-2026-115374- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 7.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N - Weakness
- CWE-347
- Updated
- 2026-11-02
EUVDEUVD-2026-108297
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.
- Record
EUVD-2026-108297- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-m6pj-594x-rw4f
Incus 7.0.0 before 7.0.2 and 7.1.0 before 7.5.0 contains a signature verification flaw in its...
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.
- Record
GHSA-m6pj-594x-rw4f- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N - Weakness
- CWE-347
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-115374- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N - Weakness
- CWE-347
- Updated
- 2026-11-02
OSV
Incus 7.0.0 before 7.0.2 and 7.1.0 before 7.5.0 Unsigned Header Bypass in Presigned S3 Upload URLs
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.
- Record
CVE-2026-115374- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-347
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-115374
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.
- Record
DEBIAN-CVE-2026-115374- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-115374
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.
- Record
UBUNTU-CVE-2026-115374- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 7.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
incusDebian:14 |
before 7.0.1-5, plus listed versions 6.0.4-26.0.4-36.0.5-16.0.5-26.0.5-3 Show 32 moreShow less6.0.5-46.0.5-56.0.5-66.0.5-76.0.5-86.0.6-16.0.6-26.0.6-36.14.0-1~exp16.15.0-1~exp16.16.0-1~exp16.17.0-1~exp16.20.0-1~exp16.21.0-1~exp16.22.0-1~exp16.23.0-1~exp17.0.0-17.0.0-1~bpo13+17.0.0-27.0.0-2~bpo13+17.0.0-37.0.0-47.0.0-57.0.0-5~bpo13+17.0.1-17.0.1-1~bpo13+17.0.1-27.0.1-2~bpo13+17.0.1-37.0.1-3~bpo13+17.0.1-47.0.1-5~bpo13+1 |
7.0.1-5 |
incusUbuntu:Pro:24.04:LTS |
All versions, plus listed versions 0.4-1ubuntu10.5.1-10.5.1-30.6-16.0.0-1 Show 7 moreShow less6.0.0-1ubuntu0.16.0.0-1ubuntu0.26.0.0-1ubuntu0.2+esm16.0.0-1ubuntu0.36.0.0-1ubuntu0.3+esm16.0.0-1ubuntu0.3+esm26.0.0-1ubuntu0.3+esm3 |
None known |
incusUbuntu:26.10 |
All versions, plus listed versions 6.0.5-87.0.1-5 |
None known |
incusUbuntu:Pro:26.04:LTS |
All versions, plus listed versions 6.0.4-26.0.5-86.0.5-8ubuntu0.26.04.1~esm1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-115374 is a high vulnerability (CVSS 7.1) in Lxc Incus, published October 22, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.18%, the 8th percentile. Fixed in incus 7.0.1-5.
References
github.com/lxc/incus/security/advisories/GHSA-mmj7-8rgf-mx2h
vulncheck.com/advisories/incus-7.0.0-before-7.0.2-and-7.1.0-before-7.5.0-unsigned-header-bypass-in-presigned-s3-upload-urls
nvd.nist.gov/vuln/detail/CVE-2026-115374
security-tracker.debian.org/tracker/CVE-2026-115374
ubuntu.com/security/CVE-2026-115374
cve.org/CVERecord?id=CVE-2026-115374