CVE-2026-52956

HIGHPre-NVD 7.57.5
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-06-24. A secondary CVSS source baseline 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, a secondary CVSS source
Trending — 4 sources updated this week

Also known asEUVD-2026-38824 (ENISA EUVD) · GHSA-wvxf-4p9h-5vg9 (GitHub Security Advisories)Source: ENISA EUVD

7.5EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.6%CVSS: 7.5Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

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

libceph: Fix potential out-of-bounds access in __ceph_x_decrypt()

In __ceph_x_decrypt(), a part of the buffer p is interpreted as a ceph_x_encrypt_header, and the magic field of this struct is accessed. This happens without any guarantee that the buffer is large enough to hold this struct. The function parameter ciphertext_len represents the length of the ciphertext to decrypt and is guaranteed to be at most the remaining size of the allocated buffer p. However, this value is not necessarily greater than sizeof(ceph_x_encrypt_header). E.g., a message frame of type FRAME_TAG_AUTH_REPLY_MORE, that is just as long to hold the ciphertext at its end with a ciphertext_len of 8 or less, can trigger an out-of-bounds memory access when accessing hdr->magic.

This patch fixes the issue by adding a check to ensure that the decrypted plaintext in the buffer is large enough to represent at least the ceph_x_encrypt_header.

CVSS v3
7.5
EG Score
7.5HIGHmedium confidence
EG Risk
49
EG Risk 49/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity75% × 45%
Impact severity (EG Severity): CVSS 7.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.6% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
0.6%
EPSS %ILE
49th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (7.5): severity, escalated by confirmed exploitation. This CVE's 7.5 is its impact severity (EG Severity), not escalated.

EG Severity
7.5 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.6% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-24). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at low or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; 60 days if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Attend at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; 60 days if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

June 24, 2026

Last Modified

October 21, 2026

Advisory Details (2)

Auto-updated Jun 28, 2026
Patch available.
Web page

libceph: Fix potential out-of-bounds access in __ceph_x_decrypt() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/c7e9b53aebe401970f1b5f5a01b4e021b18e8bb2
Web page

libceph: Fix potential out-of-bounds access in __ceph_x_decrypt() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/821365487aa58d06bda65c676ba215d506ba9768

Vendor Advisories for CVE-2026-52956(2)

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

Patch Availability(13)

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.

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
linux5.10.103-1 ... 7.2~rc5-1~exp1 (496 versions)
  • every version on: no fix on record
—
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 ... 7.0.9-1~bpo13+1 (141 versions)
  • every version up to 7.0.10-1: fixed in 7.0.10-1
—

Weakness Classification(1)

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

Additional Vendor Advisories

(12)

Data Freshness Timeline

(refreshed 14× in last 7d / 59× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 100 of 328 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 228 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  2. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  3. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  4. 2026-10-25 14:21 UTCEG score recompute
  5. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  6. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  7. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  8. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  9. 2026-10-21 13:47 UTCEG score recompute
  10. 2026-10-21 13:47 UTCVendor advisory
  11. 2026-10-21 13:47 UTCGHSA enrichmentGHSA-wvxf-4p9h-5vg9 · GitHub severity HIGH · GitHub CVSS 7.5
  12. 2026-10-21 12:56 UTCEG score recompute
  13. 2026-10-21 12:56 UTCVendor advisory
  14. 2026-10-21 12:56 UTCGHSA enrichmentGHSA-wvxf-4p9h-5vg9 · GitHub severity HIGH · GitHub CVSS 7.5
  15. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  16. 2026-10-19 20:41 UTCEG score recompute
  17. 2026-10-19 20:41 UTCVendor advisory
  18. 2026-10-19 20:41 UTCGHSA enrichmentGHSA-wvxf-4p9h-5vg9 · GitHub severity HIGH · GitHub CVSS 7.5
  19. 2026-10-19 20:09 UTCEG score recompute
  20. 2026-10-19 20:09 UTCVendor advisory
  21. 2026-10-19 20:08 UTCGHSA enrichmentGHSA-wvxf-4p9h-5vg9 · GitHub severity HIGH · GitHub CVSS 7.5
  22. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  23. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  24. 2026-10-18 03:32 UTCEG score recompute
  25. 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.6% · 48th percentile
Show 75 more
  1. 2026-10-16 17:26 UTCEG score recompute
  2. 2026-10-16 17:26 UTCVendor advisory
  3. 2026-10-16 17:26 UTCGHSA enrichmentGHSA-wvxf-4p9h-5vg9 · GitHub severity HIGH · GitHub CVSS 7.5
  4. 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  5. 2026-10-16 15:59 UTCEG score recompute
  6. 2026-10-16 15:58 UTCGHSA enrichmentGHSA-wvxf-4p9h-5vg9 · GitHub severity HIGH · GitHub CVSS 7.5
  7. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  8. 2026-10-15 11:26 UTCEG score recompute
  9. 2026-10-15 11:25 UTCGHSA enrichmentGHSA-wvxf-4p9h-5vg9 · GitHub severity HIGH · GitHub CVSS 7.5
  10. 2026-10-15 10:28 UTCEG score recompute
  11. 2026-10-15 10:28 UTCVendor advisory
  12. 2026-10-15 10:28 UTCGHSA enrichmentGHSA-wvxf-4p9h-5vg9 · GitHub severity HIGH · GitHub CVSS 7.5
  13. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  14. 2026-10-14 05:24 UTCOSV refresh
  15. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  16. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  17. 2026-10-12 15:58 UTCEG score recompute
  18. 2026-10-11 19:41 UTCEG score recompute
  19. 2026-10-11 16:56 UTCEG score recompute
  20. 2026-10-11 14:19 UTCEG score recompute
  21. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  22. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  23. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  24. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  25. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  26. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  27. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  28. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  29. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  30. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  31. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  32. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  33. 2026-09-29 15:22 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  34. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  35. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  36. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  37. 2026-09-26 00:27 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  38. 2026-09-23 17:53 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  39. 2026-09-23 11:45 UTCEG score recompute
  40. 2026-09-23 11:45 UTCVendor advisory
  41. 2026-09-23 11:45 UTCGHSA enrichmentGHSA-wvxf-4p9h-5vg9 · GitHub severity HIGH · GitHub CVSS 7.5
  42. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  43. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  44. 2026-09-18 08:08 UTCEG score recompute
  45. 2026-09-18 08:08 UTCVendor advisory
  46. 2026-09-18 08:08 UTCGHSA enrichmentGHSA-wvxf-4p9h-5vg9 · GitHub severity HIGH · GitHub CVSS 7.5
  47. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  48. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  49. 2026-09-14 01:56 UTCEG score recompute
  50. 2026-09-14 01:56 UTCVendor advisory
  51. 2026-09-14 01:56 UTCGHSA enrichmentGHSA-wvxf-4p9h-5vg9 · GitHub severity HIGH · GitHub CVSS 7.5
  52. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  53. 2026-09-13 12:01 UTCEG score recompute
  54. 2026-09-13 12:01 UTCVendor advisory
  55. 2026-09-13 12:01 UTCGHSA enrichmentGHSA-wvxf-4p9h-5vg9 · GitHub severity HIGH · GitHub CVSS 7.5
  56. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  57. 2026-09-10 09:35 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  58. 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  59. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  60. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  61. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  62. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  63. 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  64. 2026-09-01 04:40 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  65. 2026-08-30 20:19 UTCEG score recompute
  66. 2026-08-30 20:19 UTCVendor advisory
  67. 2026-08-30 20:19 UTCGHSA enrichmentGHSA-wvxf-4p9h-5vg9 · GitHub severity HIGH · GitHub CVSS 7.5
  68. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  69. 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  70. 2026-08-28 21:41 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  71. 2026-08-28 04:49 UTCEG score recompute
  72. 2026-08-28 04:49 UTCVendor advisory
  73. 2026-08-28 04:49 UTCGHSA enrichmentGHSA-wvxf-4p9h-5vg9 · GitHub severity HIGH · GitHub CVSS 7.5
  74. 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  75. 2026-08-26 14:46 UTCEPSS rescoreEPSS 0.4% · 28th percentile

Frequently asked(5)

What is CVE-2026-52956?
CVE-2026-52956 is a high-severity vulnerability; its CVE record was published on June 24, 2026. In the Linux kernel, the following vulnerability has been resolved: libceph: Fix potential out-of-bounds access in cephxdecrypt() In cephxdecrypt(), a part of the buffer p is interpreted as a cephxencrypt_header, and the magic field of this struct is accessed. This happens without any guarantee…
When was the CVE record for CVE-2026-52956 published?
The CVE record for CVE-2026-52956 was published on June 24, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of October 21, 2026; the record at its source may have been updated since.
Is CVE-2026-52956 actively exploited?
CVE-2026-52956 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.6% probability of exploitation in the next 30 days (49th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-52956?
CVE-2026-52956 has a CVSS base score of 7.5 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-52956?
A fix for CVE-2026-52956 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-52956 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-2026-52956

Explore →

Is Your Infrastructure Affected by CVE-2026-52956?

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