CVE-2026-26825

MEDIUMNVD 5.35.3—
EchelonGraph scoreMEDIUM confidence

Score 5.3 from GitHub Security Advisory published 2026-06-03. NVD baseline CVSS 5.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Trending — 3 sources updated this week
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.3Exploit: None knownExposed: 0

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

A use-of-uninitialized memory vulnerability exists in libxls 1.6.3 when parsing malformed XLS files. The issue is reachable via xls_parseWorkBook() and is triggered by uninitialized heap memory originating from the OLE layer (ole2_read). The flaw is detectable with MemorySanitizer (MSAN) and can lead to undefined behavior, incorrect parsing logic, or potential information disclosure.

CVSS v3
5.3
EG Score
5.3(medium)
EG Risk
39(Track)
EG Risk 39/100SSVC: 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
Severity53% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
12%
KEV
Not listed

Published

June 3, 2026

Last Modified

July 22, 2026

Advisory Details (1)

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

Use of Uninitialized Memory in libxls Workbook Parsing · Issue #156 · libxls/libxls · GitHub

https://github.com/libxls/libxls/issues/156

Vendor Advisories for CVE-2026-26825(1)

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

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
r-cran-readxl1.3.1-2 ... 1.5.0-1 (8 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
r-cran-readxl1.4.2-1, 1.4.3-1, 1.4.4-1, 1.4.5-1, 1.5.0-1——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
r-cran-readxl1.4.5-1, 1.5.0-1——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
r-cran-readxl1.4.5-1, 1.5.0-1——

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 13× in last 7d / 70× 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.

Showing the most recent 100 of 193 total refreshes for this CVE.

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

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-26825?
CVE-2026-26825 is a medium vulnerability published on June 3, 2026. A use-of-uninitialized memory vulnerability exists in libxls 1.6.3 when parsing malformed XLS files. The issue is reachable via xlsparseWorkBook() and is triggered by uninitialized heap memory originating from the OLE layer (ole2read). The flaw is detectable with MemorySanitizer (MSAN) and can lead…
When was CVE-2026-26825 disclosed?
CVE-2026-26825 was first published in the National Vulnerability Database on June 3, 2026, with the most recent update on July 22, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-26825 actively exploited?
CVE-2026-26825 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 88.4% of all scored CVEs.
What is the CVSS score of CVE-2026-26825?
CVE-2026-26825 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-26825?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-26825, 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.

Dependency Blast Radius

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