CVE-2026-90263

UNRATEDCVSS · not yet scoredTrending — 4 sources updated this week
—
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • No CVSS published and no exploitation signals yet
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS v2: —Exploit: None knownExposed services: Not assessed

No fix is confirmed yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for the fix.

In the Linux kernel, the following vulnerability has been resolved:

btrfs: check if root is readonly when setting posix acl

For a filesystem which has btrfs read-only property set to true, all write operations including acl and xattr should be denied. However, acl can still be set even if btrfs ro property is true.

This happens because no function on the set_acl code path checks the root is readonly or not. It was checked in btrfs_setxattr_trans() but got removed in commit 353c2ea735e4 ("btrfs: remove redundant readonly root check in btrfs_setxattr_trans")

That commit didn't check if all the callers properly check the root's read-only flag. A previous fix is commit b51111271b03 ("btrfs: check if root is readonly while setting security xattr").

Always check if the root is read-only before performing the set acl operation.

CVSS v3
—
EchelonGraph score
Not yet assessedNo source has published severity data for this CVE yet — no CVSS score from NVD or a CNA, no GitHub advisory, and it is not in CISA KEV. This is not a rating of zero; we cannot assess it yet.
EG Score
—
EG Risk
—
EPSS PROB
0.2%
EPSS %ILE
8th
KEV
Not listed

Published

September 17, 2026

Last Modified

September 17, 2026

References (2)

Vendor Advisories for CVE-2026-90263(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
linux6.1.106-1 ... 7.2~rc7-1~exp1 (358 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
linux6.12.100-1 ... 7.2~rc7-1~exp1 (181 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
linux6.12.100-1 ... 7.2~rc7-1~exp1 (178 versions)
  • every version up to 7.2.6-1: fixed in 7.2.6-1
—

Data Freshness Timeline

(refreshed 12× in last 7d / 29× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-10-04 23:22 UTCEPSS rescore
  2. 2026-10-03 23:57 UTCVendor advisory
  3. 2026-10-03 23:57 UTCGHSA enrichment
  4. 2026-10-01 19:51 UTCEPSS rescore
  5. 2026-10-01 06:55 UTCEG score recompute
  6. 2026-10-01 06:55 UTCVendor advisory
  7. 2026-10-01 06:55 UTCGHSA enrichment
  8. 2026-09-30 15:04 UTCEPSS rescore
  9. 2026-09-28 13:54 UTCVendor advisory
  10. 2026-09-28 13:54 UTCGHSA enrichment
  11. 2026-09-28 13:52 UTCEPSS rescore
  12. 2026-09-28 13:52 UTCEPSS rescore
  13. 2026-09-27 13:49 UTCEPSS rescore
  14. 2026-09-26 15:59 UTCEPSS rescore
  15. 2026-09-25 20:53 UTCVendor advisory
  16. 2026-09-25 20:53 UTCGHSA enrichment
  17. 2026-09-24 14:04 UTCEPSS rescore
  18. 2026-09-23 03:51 UTCVendor advisory
  19. 2026-09-23 03:51 UTCGHSA enrichment
  20. 2026-09-22 16:01 UTCEPSS rescore
  21. 2026-09-21 21:09 UTCEPSS rescore
  22. 2026-09-20 20:16 UTCEPSS rescore
  23. 2026-09-20 10:50 UTCEG score recompute
  24. 2026-09-20 10:50 UTCVendor advisory
  25. 2026-09-20 10:50 UTCGHSA enrichment
Show 4 more
  1. 2026-09-18 19:28 UTCEPSS rescore
  2. 2026-09-17 17:24 UTCNVD update
  3. 2026-09-17 16:35 UTCEG score recompute
  4. 2026-09-17 16:19 UTCMITRE cvelistV5first tracked

Frequently asked(4)

What is CVE-2026-90263?
CVE-2026-90263 is a publicly disclosed vulnerability published on September 17, 2026. In the Linux kernel, the following vulnerability has been resolved: btrfs: check if root is readonly when setting posix acl For a filesystem which has btrfs read-only property set to true, all write operations including acl and xattr should be denied. However, acl can still be set even if btrfs ro…
When was CVE-2026-90263 disclosed?
CVE-2026-90263 was first published on September 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-90263 actively exploited?
CVE-2026-90263 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (8th percentile of EPSS-scored CVEs).
How do I remediate CVE-2026-90263?
No fix for CVE-2026-90263 is confirmed yet. Until one is published, restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and watch the vendor's advisory for the fix. The vendor advisories EchelonGraph has for CVE-2026-90263 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-90263

Explore →

Is Your Infrastructure Affected by CVE-2026-90263?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Book a Demo →Browse All CVEs