CVE-2026-29964

MEDIUMNVD 6.16.1—
EchelonGraph scoreMEDIUM confidence

Score 6.1 from GitHub Security Advisory published 2026-05-18. NVD baseline CVSS 6.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
6.1
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 6.1Exploit: NoneExposed: 0

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

HSC MailInspector v5.3.3-7 contains a Cross-Site Scripting (XSS) vulnerability in the /tap/tap.php endpoint due to improper neutralization of user-controlled input using alternate or obfuscated JavaScript syntax. The endpoint reflects unsanitized user input in HTTP responses without adequate output encoding, allowing a remote attacker to execute arbitrary JavaScript code in the context of a victim's browser.

CVSS v3
6.1
EG Score
6.1(medium)
EPSS
15.5%
KEV
Not listed

Published

May 18, 2026

Last Modified

May 19, 2026

Advisory Details (3)

Auto-updated Jun 13, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic

Solução de Segurança de E-mail - Mailinspector - HSC Labs

https://hsclabs.com/pt-br/mailinspector/
generic

cve-disclosures/03_-_CVE-2026-29964_XSS.md at main · sql3t0/cve-disclosures · GitHub

https://github.com/sql3t0/cve-disclosures/blob/main/03_-_CVE-2026-29964_XSS.md
generic🟡 PoC Available

GitHub - sql3t0/cve-disclosures: Collection of CVEs and security advisories discovered and responsibly disclosed by Sql3t0, including technical details, impact assessment, and mitigation guidance. · GitHub

https://github.com/sql3t0/cve-disclosures

Vendor Advisories for CVE-2026-29964(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 10× in last 7d / 57× 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 141 total refreshes for this CVE.

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

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-29964?
CVE-2026-29964 is a medium vulnerability published on May 18, 2026. HSC MailInspector v5.3.3-7 contains a Cross-Site Scripting (XSS) vulnerability in the /tap/tap.php endpoint due to improper neutralization of user-controlled input using alternate or obfuscated JavaScript syntax. The endpoint reflects unsanitized user input in HTTP responses without adequate output…
When was CVE-2026-29964 disclosed?
CVE-2026-29964 was first published in the National Vulnerability Database on May 18, 2026, with the most recent update on May 19, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-29964 actively exploited?
CVE-2026-29964 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 15.5% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-29964?
CVE-2026-29964 has a CVSS v3 base score of 6.1 (NVD).
How do I remediate CVE-2026-29964?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-29964, 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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