CVE-2026-52961

MEDIUMNVD 5.55.5—
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2026-06-24. NVD baseline CVSS 5.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Trending — 4 sources updated this week
5.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.5Exploit: None knownExposed: 0

A fix is available — apply it.

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

ceph: fix BUG_ON in __ceph_build_xattrs_blob() due to stale blob size

The generic/642 test-case can reproduce the kernel crash:

[40243.605254] ------------[ cut here ]------------ [40243.605956] kernel BUG at fs/ceph/xattr.c:918! [40243.607142] Oops: invalid opcode: 0000 [#1] SMP PTI [40243.608067] CPU: 7 UID: 0 PID: 498762 Comm: kworker/7:1 Not tainted 7.0.0-rc7+ #3 PREEMPT(full) [40243.609700] Hardware name: QEMU Ubuntu 25.10 PC v2 (i440FX + PIIX, + 10.1 machine, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [40243.611820] Workqueue: ceph-msgr ceph_con_workfn [40243.612715] RIP: 0010:__ceph_build_xattrs_blob+0x1b8/0x1e0 [40243.613731] Code: 0f 84 82 fe ff ff e9 cf 8e 56 ff 48 8d 65 e8 31 c0 5b 41 5c 41 5d 5d 31 d2 31 c9 31 f6 31 ff 45 31 c0 45 31 c9 c3 cc cc cc cc <0f> 0b 4c 8b 62 08 41 8b 85 24 07 00 00 49 83 c4 04 41 89 44 24 fc [40243.616888] RSP: 0018:ffffcc80c4d4b688 EFLAGS: 00010287 [40243.617773] RAX: 0000000000010026 RBX: 0000000000000001 RCX: 0000000000000000 [40243.618928] RDX: ffff8a773798dee0 RSI: 0000000000000000 RDI: 0000000000000000 [40243.620158] RBP: ffffcc80c4d4b6a0 R08: 0000000000000000 R09: 0000000000000000 [40243.621573] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8a75f3b58000 [40243.622907] R13: ffff8a75f3b58000 R14: 0000000000000080 R15: 000000000000bffd [40243.624054] FS: 0000000000000000(0000) GS:ffff8a787d1b4000(0000) knlGS:0000000000000000 [40243.625331] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [40243.626269] CR2: 000072f390b623c0 CR3: 000000011c02a003 CR4: 0000000000372ef0 [40243.627408] Call Trace: [40243.627839] [40243.628188] __prep_cap+0x3fd/0x4a0 [40243.628789] ? do_raw_spin_unlock+0x4e/0xe0 [40243.629474] ceph_check_caps+0x46a/0xc80 [40243.630094] ? __lock_acquire+0x4a2/0x2650 [40243.630773] ? find_held_lock+0x31/0x90 [40243.631347] ? handle_cap_grant+0x79f/0x1060 [40243.632068] ? lock_release+0xd9/0x300 [40243.632696] ? __mutex_unlock_slowpath+0x3e/0x340 [40243.633429] ? lock_release+0xd9/0x300 [40243.634052] handle_cap_grant+0xcf6/0x1060 [40243.634745] ceph_handle_caps+0x122b/0x2110 [40243.635415] mds_dispatch+0x5bd/0x2160 [40243.636034] ? ceph_con_process_message+0x65/0x190 [40243.636828] ? lock_release+0xd9/0x300 [40243.637431] ceph_con_process_message+0x7a/0x190 [40243.638184] ? kfree+0x311/0x4f0 [40243.638749] ? kfree+0x311/0x4f0 [40243.639268] process_message+0x16/0x1a0 [40243.639915] ? sg_free_table+0x39/0x90 [40243.640572] ceph_con_v2_try_read+0xf58/0x2120 [40243.641255] ? lock_acquire+0xc8/0x300 [40243.641863] ceph_con_workfn+0x151/0x820 [40243.642493] process_one_work+0x22f/0x630 [40243.643093] ? process_one_work+0x254/0x630 [40243.643770] worker_thread+0x1e2/0x400 [40243.644332] ? __pfx_worker_thread+0x10/0x10 [40243.645020] kthread+0x109/0x140 [40243.645560] ? __pfx_kthread+0x10/0x10 [40243.646125] ret_from_fork+0x3f8/0x480 [40243.646752] ? __pfx_kthread+0x10/0x10 [40243.647316] ? __pfx_kthread+0x10/0x10 [40243.647919] ret_from_fork_asm+0x1a/0x30 [40243.648556] [40243.648902] Modules linked in: overlay hctr2 libpolyval chacha libchacha adiantum libnh libpoly1305 essiv intel_rapl_msr intel_rapl_common intel_uncore_frequency_common skx_edac_common nfit kvm_intel kvm irqbypass joydev ghash_clmulni_intel aesni_intel rapl input_leds mac_hid psmouse vga16fb serio_raw vgastate floppy i2c_piix4 pata_acpi bochs qemu_fw_cfg i2c_smbus sch_fq_codel rbd dm_crypt msr parport_pc ppdev lp parport efi_pstore [40243.654766] ---[ end trace 0000000000000000 ]---

Commit d93231a6bc8a ("ceph: prevent a client from exceeding the MDS maximum xattr size") moved the required_blob_size computation to before the __build_xattrs() call, introducing a race.

__build_xattrs() releases and reacquires i_ceph_lock during execution. In that window, handle_cap_grant() may update i_xattrs.blob with a newer MDS-provided blob and bump i_xattrs.version. When __bui ---truncated---

CVSS v3
5.5
EG Score
5.5(medium)
EG Risk
29(Track)
EG Risk 29/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity55% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
4%
KEV
Not listed

Published

June 24, 2026

Last Modified

July 14, 2026

Advisory Details (4)

Auto-updated Jul 15, 2026
No patch confirmed yet.
generic

ceph: fix BUG_ON in __ceph_build_xattrs_blob() due to stale blob size - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d5bd8b4e39cfa8b087448adcd48088065cd629d5
generic

ceph: fix BUG_ON in __ceph_build_xattrs_blob() due to stale blob size - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/7eb72425c4e3234926502eb262f9d6193ccd572c
generic

ceph: fix BUG_ON in __ceph_build_xattrs_blob() due to stale blob size - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/368d21ae9081c93497b1c8163bed3eddcb2443ff
generic

ceph: fix BUG_ON in __ceph_build_xattrs_blob() due to stale blob size - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/0c22d9511cbde746622f8e4c11aaa63fe76d45f9

Vendor Advisories for CVE-2026-52961(2)

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

Patch Availability(15)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-tools-azure-edge (6.8.0-1063.71~22.04.1) @ jammy2026-07-26ubuntu
ubuntulinux-tools-azure-fde-lts-24.04 (6.8.0-1062.69) @ noble2026-07-26ubuntu
ubuntulinux-tools-azure-fips-6.8 (6.8.0-1063.71+fips2) @ noble2026-07-26ubuntu
ubuntulinux-tools-azure-fde-6.8 (6.8.0-1062.69~22.04.1) @ jammy2026-07-26ubuntu
ubuntulinux-virtual-hwe-24.04-edge (7.0.0-28.28~24.04.1) @ noble2026-07-26ubuntu
ubuntulinux-tools-oem-7.0 (7.0.0-1009.9) @ resolute2026-07-26ubuntu
ubuntulinux-tools-oracle-7.0 (7.0.0-1008.8) @ resolute2026-07-26ubuntu
ubuntulinux-tools-realtime-hwe-22.04 (6.8.1-1056.57~22.04.2) @ jammy2026-07-26ubuntu
ubuntulinux-tools-gcp-fips-6.8 (6.8.0-1064.72+fips1) @ noble2026-07-26ubuntu
ubuntulinux-tools-oracle-lts-24.04 (6.8.0-1058.61) @ noble2026-07-26ubuntu
ubuntulinux-tools-azure-fde-7.0 (7.0.0-1009.9) @ resolute2026-07-26ubuntu
ubuntulinux-virtual-hwe-26.04-edge (7.0.0-28.28) @ resolute2026-07-26ubuntu
ubuntulinux-tools-oracle-edge (6.8.0-1058.61~22.04.1) @ jammy2026-07-26ubuntu
ubuntulinux-tools-aws-lts-24.04 (6.8.0-1061.64+1) @ noble2026-07-26ubuntu
ubuntulinux-tools-nvidia-lowlatency-64k-6.8 (6.8.0-1059.62.1) @ noble2026-07-26ubuntu

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(15)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 11× in last 7d / 52× 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. 2026-07-27 17:40 UTCEG score recompute
  2. 2026-07-27 17:40 UTCGHSA enrichment
  3. 2026-07-26 15:42 UTCEG score recompute
  4. 2026-07-26 15:42 UTCVendor advisory
  5. 2026-07-26 15:41 UTCGHSA enrichment
  6. 2026-07-26 14:54 UTCEPSS rescore
  7. 2026-07-24 14:18 UTCEPSS rescore
  8. 2026-07-23 14:18 UTCEPSS rescore
  9. 2026-07-23 03:19 UTCEG score recompute
  10. 2026-07-22 14:08 UTCEPSS rescore
  11. 2026-07-21 15:25 UTCEPSS rescore
  12. 2026-07-20 17:08 UTCEPSS rescore
  13. 2026-07-19 14:31 UTCEPSS rescore
  14. 2026-07-19 14:31 UTCEPSS rescore
  15. 2026-07-18 10:04 UTCEPSS rescore
  16. 2026-07-16 17:03 UTCEPSS rescore
  17. 2026-07-16 11:25 UTCGHSA enrichment
  18. 2026-07-15 16:57 UTCEPSS rescore
  19. 2026-07-15 16:57 UTCEPSS rescore
  20. 2026-07-15 09:48 UTCEG score recompute▲ 5.50
  21. 2026-07-15 09:48 UTCGHSA enrichment
  22. 2026-07-15 02:00 UTCEPSS rescore
  23. 2026-07-15 02:00 UTCEPSS rescore
  24. 2026-07-14 17:20 UTCNVD updateCVSS v3 → 5.5 · severity → MEDIUM
  25. 2026-07-13 22:31 UTCEPSS rescore
Show 34 more
  1. 2026-07-13 06:13 UTCEPSS rescore
  2. 2026-07-13 06:13 UTCEPSS rescore
  3. 2026-07-12 11:03 UTCGHSA enrichment
  4. 2026-07-12 05:46 UTCEPSS rescore
  5. 2026-07-11 08:27 UTCEPSS rescore
  6. 2026-07-11 08:27 UTCEPSS rescore
  7. 2026-07-09 19:10 UTCEPSS rescore
  8. 2026-07-09 19:10 UTCEPSS rescore
  9. 2026-07-09 12:18 UTCGHSA enrichment
  10. 2026-07-08 15:16 UTCEPSS rescore
  11. 2026-07-08 15:16 UTCEPSS rescore
  12. 2026-07-07 13:46 UTCEPSS rescore
  13. 2026-07-07 13:46 UTCEPSS rescore
  14. 2026-07-06 16:27 UTCEPSS rescore
  15. 2026-07-06 16:27 UTCEPSS rescore
  16. 2026-07-06 13:31 UTCGHSA enrichment
  17. 2026-07-06 02:23 UTCEPSS rescore
  18. 2026-07-06 02:23 UTCEPSS rescore
  19. 2026-07-05 02:30 UTCEPSS rescore
  20. 2026-07-04 06:31 UTCEPSS rescore
  21. 2026-07-03 14:42 UTCGHSA enrichment
  22. 2026-07-01 15:07 UTCEPSS rescore
  23. 2026-06-30 23:22 UTCEPSS rescore
  24. 2026-06-30 15:57 UTCGHSA enrichment
  25. 2026-06-29 14:06 UTCEPSS rescore
  26. 2026-06-29 14:06 UTCEPSS rescore
  27. 2026-06-28 14:07 UTCEPSS rescore
  28. 2026-06-28 04:56 UTCEPSS rescore
  29. 2026-06-28 04:56 UTCEPSS rescore
  30. 2026-06-27 17:13 UTCGHSA enrichment
  31. 2026-06-27 03:08 UTCEPSS rescore
  32. 2026-06-25 13:49 UTCEPSS rescore
  33. 2026-06-24 18:29 UTCEG score recompute
  34. 2026-06-24 18:02 UTCNVD updatefirst tracked

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-52961?
CVE-2026-52961 is a medium vulnerability published on June 24, 2026. In the Linux kernel, the following vulnerability has been resolved: ceph: fix BUGON in cephbuildxattrsblob() due to stale blob size The generic/642 test-case can reproduce the kernel crash: [40243.605254] ------------[ cut here ]------------ [40243.605956] kernel BUG at fs/ceph/xattr.c:918!…
When was CVE-2026-52961 disclosed?
CVE-2026-52961 was first published in the National Vulnerability Database on June 24, 2026, with the most recent update on July 14, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-52961 actively exploited?
CVE-2026-52961 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 95.9% of all scored CVEs.
What is the CVSS score of CVE-2026-52961?
CVE-2026-52961 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-52961?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-52961, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

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