CVE-2026-18839

LOWPre-NVD 2.22.2—
EchelonGraph scoreMEDIUM confidence

Score 2.2 from GitHub Security Advisory (severity: LOW) published 2026-08-05. A secondary CVSS source baseline 2.2; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
2.2EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.1%CVSS: 2.2Exploit: None knownExposed services: Not assessed

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

An integer underflow was found in the popt library when formatting help text for option tables that exceed the terminal width. A local user who can cause an application to print help under those conditions may cause that application to crash or fail to display help, resulting in a denial of service of the affected application.

CVSS v3
2.2
EG Score
2.2LOWmedium confidence
EG Risk
10
EG Risk 10/100CISA SSVC

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
Severity22% × 45%
Exploitation0% × 40%
Automatability0% × 15%
CISA SSVC: Track at every mission impact level.
Action: No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines, and watch the vendor's advisory for the fix.
EPSS PROB
0.1%
EPSS %ILE
1st
KEV
Not listed

CISA SSVCTrack at every mission impact level.

No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines, and watch the vendor's advisory for the fix.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

August 5, 2026

Last Modified

September 1, 2026

References (2)

Vendor Advisories for CVE-2026-18839(2)

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
popt1.18-2, 1.18-3, 1.19+dfsg-1, 1.19+dfsg-1~exp1, 1.19+dfsg-2
  • every version on: no fix on record
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
popt1.19+dfsg-1, 1.19+dfsg-2
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
popt1.19+dfsg-2
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
popt1.19+dfsg-2
  • 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 10× in last 7d / 38× 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.

  1. 2026-10-04 23:21 UTCEPSS rescore
  2. 2026-10-04 05:57 UTCEG score recompute
  3. 2026-10-04 05:57 UTCVendor advisory
  4. 2026-10-04 05:57 UTCGHSA enrichment
  5. 2026-10-01 19:49 UTCEPSS rescore
  6. 2026-10-01 02:14 UTCEG score recompute
  7. 2026-10-01 02:14 UTCVendor advisory
  8. 2026-10-01 02:14 UTCGHSA enrichment
  9. 2026-09-30 15:02 UTCEPSS rescore
  10. 2026-09-29 15:20 UTCEPSS rescore
  11. 2026-09-28 13:51 UTCEPSS rescore
  12. 2026-09-27 17:38 UTCEG score recompute
  13. 2026-09-27 17:38 UTCVendor advisory
  14. 2026-09-27 17:38 UTCGHSA enrichment
  15. 2026-09-27 13:47 UTCEPSS rescore
  16. 2026-09-23 05:14 UTCVendor advisory
  17. 2026-09-23 05:14 UTCGHSA enrichment
  18. 2026-09-20 03:13 UTCEG score recompute
  19. 2026-09-20 03:13 UTCVendor advisory
  20. 2026-09-20 03:13 UTCGHSA enrichment
  21. 2026-09-17 01:04 UTCEG score recompute
  22. 2026-09-17 01:04 UTCVendor advisory
  23. 2026-09-17 01:04 UTCGHSA enrichment
  24. 2026-09-16 14:07 UTCEPSS rescore
  25. 2026-09-16 05:14 UTCEPSS rescore
Show 66 more
  1. 2026-09-13 22:14 UTCEG score recompute
  2. 2026-09-13 22:14 UTCVendor advisory
  3. 2026-09-13 22:14 UTCGHSA enrichment
  4. 2026-09-12 15:00 UTCEPSS rescore
  5. 2026-09-11 14:52 UTCEPSS rescore
  6. 2026-09-11 09:36 UTCEPSS rescore
  7. 2026-09-10 20:12 UTCEG score recompute
  8. 2026-09-10 20:12 UTCGHSA enrichment
  9. 2026-09-10 09:34 UTCEPSS rescore
  10. 2026-09-08 22:00 UTCEPSS rescore
  11. 2026-09-07 18:10 UTCEG score recompute
  12. 2026-09-07 18:10 UTCGHSA enrichment
  13. 2026-09-06 13:47 UTCEPSS rescore
  14. 2026-09-04 15:53 UTCEG score recompute
  15. 2026-09-04 15:53 UTCGHSA enrichment
  16. 2026-09-04 05:06 UTCEPSS rescore
  17. 2026-09-01 13:53 UTCEPSS rescore
  18. 2026-09-01 13:42 UTCEG score recompute
  19. 2026-09-01 13:42 UTCGHSA enrichment
  20. 2026-09-01 13:17 UTCEG score recompute
  21. 2026-09-01 13:17 UTCGHSA enrichment
  22. 2026-09-01 04:39 UTCEPSS rescore
  23. 2026-08-31 16:40 UTCEG score recompute
  24. 2026-08-31 16:40 UTCGHSA enrichment
  25. 2026-08-31 15:38 UTCEG score recompute
  26. 2026-08-31 15:38 UTCGHSA enrichment
  27. 2026-08-30 21:55 UTCGHSA enrichment
  28. 2026-08-27 19:54 UTCEG score recompute
  29. 2026-08-27 19:54 UTCGHSA enrichment
  30. 2026-08-27 14:25 UTCEPSS rescore
  31. 2026-08-26 14:46 UTCEPSS rescore
  32. 2026-08-25 13:48 UTCEPSS rescore
  33. 2026-08-24 15:23 UTCEG score recompute
  34. 2026-08-24 15:22 UTCGHSA enrichment
  35. 2026-08-23 00:19 UTCEPSS rescore
  36. 2026-08-21 23:49 UTCEPSS rescore
  37. 2026-08-21 13:21 UTCEG score recompute
  38. 2026-08-21 13:21 UTCGHSA enrichment
  39. 2026-08-21 13:09 UTCEG score recompute
  40. 2026-08-21 13:09 UTCGHSA enrichment
  41. 2026-08-19 17:03 UTCEPSS rescore
  42. 2026-08-18 23:53 UTCEG score recompute
  43. 2026-08-18 23:53 UTCGHSA enrichment
  44. 2026-08-18 13:48 UTCEPSS rescore
  45. 2026-08-17 13:47 UTCEPSS rescore
  46. 2026-08-16 02:14 UTCEPSS rescore
  47. 2026-08-15 21:52 UTCGHSA enrichment
  48. 2026-08-12 19:50 UTCEG score recompute
  49. 2026-08-12 19:50 UTCGHSA enrichment
  50. 2026-08-12 13:50 UTCEPSS rescore
  51. 2026-08-09 17:49 UTCEG score recompute
  52. 2026-08-09 17:49 UTCGHSA enrichment
  53. 2026-08-08 16:37 UTCEPSS rescore
  54. 2026-08-06 15:48 UTCGHSA enrichment
  55. 2026-08-06 14:17 UTCEG score recompute
  56. 2026-08-06 14:17 UTCGHSA enrichment
  57. 2026-08-06 13:53 UTCEG score recompute
  58. 2026-08-06 13:53 UTCGHSA enrichment
  59. 2026-08-06 13:46 UTCEPSS rescore
  60. 2026-08-05 22:18 UTCEG score recompute
  61. 2026-08-05 22:18 UTCGHSA enrichment
  62. 2026-08-05 22:05 UTCEG score recompute
  63. 2026-08-05 22:05 UTCGHSA enrichment
  64. 2026-08-05 21:17 UTCEG score recompute
  65. 2026-08-05 21:10 UTCEG score recompute
  66. 2026-08-05 21:10 UTCMITRE cvelistV5first tracked

Related CVEs(same product + same CWE)

Same product

2 shown

Debian:11:popt · Debian:12:popt

Frequently asked(5)

What is CVE-2026-18839?
CVE-2026-18839 is a low vulnerability published on August 5, 2026. An integer underflow was found in the popt library when formatting help text for option tables that exceed the terminal width. A local user who can cause an application to print help under those conditions may cause that application to crash or fail to display help, resulting in a denial of service…
When was CVE-2026-18839 disclosed?
CVE-2026-18839 was first published on August 5, 2026, with the most recent update on September 1, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-18839 actively exploited?
CVE-2026-18839 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.1% probability of exploitation in the next 30 days (1st percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-18839?
CVE-2026-18839 has a CVSS base score of 2.2 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-18839?
No fix for CVE-2026-18839 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-2026-18839 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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