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
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 5.3Exploit: None knownExposed services: Not assessed

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

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
5.3MEDIUMmedium confidence
EG Risk
39
EG Risk 39/100

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%
EPSS PROB
0.4%
EPSS %ILE
32nd
KEV
Not listed

Published

June 3, 2026

Last Modified

September 23, 2026

Advisory Details (1)

Auto-updated Jun 15, 2026
No fix on record 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 rangeFix by version rangeDependents
r-cran-readxl1.3.1-2 ... 1.5.0-1 (8 versions)
  • every version on: no fix on record
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
r-cran-readxl1.4.2-1 ... 1.5.0.1-1 (6 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
r-cran-readxl1.4.5-1, 1.5.0-1, 1.5.0.1-1
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
r-cran-readxl1.4.5-1, 1.5.0-1, 1.5.0.1-1
  • every version on: no fix on record
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 28× 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 233 total refreshes for this CVE.

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

Related CVEs(same product + 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 on June 3, 2026, with the most recent update on September 23, 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 0.4% probability of exploitation in the next 30 days (32nd percentile of EPSS-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?
No fix for CVE-2026-26825 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-2026-26825 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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