CVE-2026-34621

HIGHNVD 8.69.6▲
EchelonGraph scoreHIGH confidence

Score elevated to 9.6 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2026-04-13), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 8.6 retained for reference. Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: cisa_kev, epss, ghsa, nvd
Trending — 4 sources updated this weekExploited in the wild
8.6
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS: 7%CVSS: 8.6Exploit: NoneExposed: 0

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

Acrobat Reader versions 24.001.30356, 26.001.21367 and earlier are affected by an Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.

CVSS v3
8.6
EG Score
9.6(high)
EG Risk
83(Attend)
EG Risk 83/100SSVC: Attend

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
Severity96% × 45%
Exploitation100% × 40%
Automatability0% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS
93.6%
KEV
⚠ Exploited

Published

April 11, 2026

Last Modified

April 13, 2026

Advisory Details (1)

Auto-updated May 19, 2026
⚠️ Active exploitation confirmed. Patch available. Sources: cisa.
cisa Patch Available🔴 Active Exploitation

Known Exploited Vulnerabilities Catalog | CISA

Known Exploited Vulnerabilities Catalog | CISA. Listed in CISA Known Exploited Vulnerabilities catalog.

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-34621

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 55× in last 7d / 231× 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 451 total refreshes for this CVE.

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

Publicly available exploits

(1 reference)

Working exploit code is in the public domain (1 GitHub PoC). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCazefzafyoussef/CVE-2026-34621
    First seen May 12, 2026
    Open source ↗

Related CVEs(same CWE)

Frequently asked(6)

What is CVE-2026-34621?
CVE-2026-34621 is a high vulnerability published on April 11, 2026. Acrobat Reader versions 24.001.30356, 26.001.21367 and earlier are affected by an Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue…
When was CVE-2026-34621 disclosed?
CVE-2026-34621 was first published in the National Vulnerability Database on April 11, 2026, with the most recent update on April 13, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-34621 actively exploited?
Yes. CISA added CVE-2026-34621 to the Known Exploited Vulnerabilities catalog on April 13, 2026, affecting Adobe Acrobat and Reader. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.
What is the CVSS score of CVE-2026-34621?
CVE-2026-34621 has a CVSS v3 base score of 8.6 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.6.
Which products are affected by CVE-2026-34621?
CVE-2026-34621 affects Adobe Acrobat and Reader. The full affected-products list, including version ranges and fixed versions, is shown in the Affected Packages section of this page.
How do I remediate CVE-2026-34621?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-34621, 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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