CVE-2026-40016

MEDIUMNVD 5.35.3—
EchelonGraph scoreMEDIUM confidence

Score 5.3 from GitHub Security Advisory published 2026-05-12. 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%CVSS: 5.3Exploit: None knownExposed: 0

A fix is available — apply it.

Attacker can upload a malicious Sieve script over ManageSieve service (or locally) to bypass configured CPU time limits for Sieve up to 130 times of the configured limit. Attacker can use this to degrade server performance and bypass configured CPU time limits for Sieve scripts. Install fixed version, or alternatively prevent direct access to Sieve scripts via ManageSieve or local access. No publicly available exploits are known.

CVSS v3
5.3
EG Score
5.3(medium)
EG Risk
24(Track)
EG Risk 24/100SSVC: 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%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
27%
KEV
Not listed

Published

May 12, 2026

Last Modified

May 18, 2026

Advisory Details (1)

Auto-updated Jun 16, 2026
No patch confirmed yet.
generic
https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0002.json

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntudovecot-submissiond (1:2.3.21+dfsg1-2ubuntu6.5) @ noble2026-08-23ubuntu

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

(6 across 6 ecosystems)
Alpine:v3.23(1)
PackageVulnerable rangeFixed inDependents
dovecot—2.4.4-r0—
Alpine:v3.24(1)
PackageVulnerable rangeFixed inDependents
dovecot—2.4.4-r0—
Debian:11(1)
PackageVulnerable rangeFixed inDependents
dovecot1:2.3.13+dfsg1-2 ... 1:2.4.4+dfsg1-2 (47 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
dovecot1:2.3.19.1+dfsg1-2.1 ... 1:2.3.19.1+dfsg1-2.1+deb12u5 (6 versions)1:2.3.19.1+dfsg1-2.1+deb12u6—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
dovecot1:2.4.1+dfsg1-6 ... 1:2.4.1+dfsg1-6+deb13u5 (6 versions)1:2.4.1+dfsg1-6+deb13u6—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
dovecot1:2.4.1+dfsg1-6 ... 1:2.4.3+dfsg1-2 (10 versions)1:2.4.4+dfsg1-1—

Weakness Classification(1)

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

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 8× in last 7d / 33× 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 219 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-40016?
CVE-2026-40016 is a medium vulnerability published on May 12, 2026. Attacker can upload a malicious Sieve script over ManageSieve service (or locally) to bypass configured CPU time limits for Sieve up to 130 times of the configured limit. Attacker can use this to degrade server performance and bypass configured CPU time limits for Sieve scripts. Install fixed…
When was CVE-2026-40016 disclosed?
CVE-2026-40016 was first published in the National Vulnerability Database on May 12, 2026, with the most recent update on May 18, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-40016 actively exploited?
CVE-2026-40016 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 73.1% of all scored CVEs.
What is the CVSS score of CVE-2026-40016?
CVE-2026-40016 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-40016?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-40016, 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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