CVE-2016-15059

CRITICALPre-NVD 9.89.8—
EchelonGraph scoreHIGH confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-09-22. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 3 sources updated this week
9.8EG
EchelonGraph verdictPlan mitigationSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 9.8Exploit: None knownExposed services: Not assessed

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

Net::IDN::Punycode versions before 2.301 for Perl allow a heap buffer overflow via unchecked writes past the output buffer in encode_punycode.

The XS backend builds the encoded label in the string buffer of the scalar it returns, sized from the input length. The loop that emits the digits of each code point checks for room before every write, but the write of the last digit of each round and the write of the terminating NUL do not, so an input whose encoded form fills the buffer writes past its end.

Only the XS backend is affected.

Encoding an attacker-supplied string corrupts the heap.

CVSS v3
9.8
EG Score
9.8CRITICALhigh confidence
EG Risk
59
EG Risk 59/100CISA 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
Severity98% × 45%
Exploitation0% × 40%
Automatability100% × 15%
CISA SSVC: Track at low or medium mission impact; Attend at high (mission-essential systems).
Action: No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.
EPSS PROB
0.4%
EPSS %ILE
33rd
KEV
Not listed

CISA SSVCTrack at low or medium mission impact; Attend at high (mission-essential systems).

No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.

Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (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

September 22, 2026

Last Modified

September 22, 2026

Advisory Details (3)

Auto-updated Sep 29, 2026
No patch confirmed yet.
generic

oss-security - CVE-2016-15059: Net::IDN::Punycode versions before 2.301 for Perl allow a heap buffer overflow via unchecked writes past the output buffer in encode_punycode

http://www.openwall.com/lists/oss-security/2026/09/22/10

Vendor Advisories for CVE-2016-15059(1)

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

Affected Packages

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
libnet-idn-encode-perl—
  • every version up to 2.303-1: fixed in 2.303-1
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
libnet-idn-encode-perl—
  • every version up to 2.303-1: fixed in 2.303-1
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
libnet-idn-encode-perl—
  • every version up to 2.303-1: fixed in 2.303-1
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 51× in last 7d / 103× 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 103 total refreshes for this CVE.

  1. 2026-10-05 06:04 UTCGHSA enrichment
  2. 2026-10-05 01:45 UTCEG score recompute
  3. 2026-10-05 01:45 UTCGHSA enrichment
  4. 2026-10-04 23:17 UTCEPSS rescore
  5. 2026-10-04 21:26 UTCGHSA enrichment
  6. 2026-10-04 17:07 UTCGHSA enrichment
  7. 2026-10-04 12:45 UTCGHSA enrichment
  8. 2026-10-04 08:27 UTCGHSA enrichment
  9. 2026-10-04 04:07 UTCGHSA enrichment
  10. 2026-10-03 23:49 UTCGHSA enrichment
  11. 2026-10-03 19:28 UTCGHSA enrichment
  12. 2026-10-03 15:09 UTCEG score recompute
  13. 2026-10-03 15:09 UTCGHSA enrichment
  14. 2026-10-03 14:21 UTCEPSS rescore
  15. 2026-10-03 10:51 UTCGHSA enrichment
  16. 2026-10-03 06:32 UTCGHSA enrichment
  17. 2026-10-03 02:13 UTCGHSA enrichment
  18. 2026-10-02 21:54 UTCGHSA enrichment
  19. 2026-10-02 17:34 UTCEG score recompute
  20. 2026-10-02 17:34 UTCGHSA enrichment
  21. 2026-10-02 13:15 UTCGHSA enrichment
  22. 2026-10-02 08:55 UTCGHSA enrichment
  23. 2026-10-02 04:33 UTCGHSA enrichment
  24. 2026-10-02 00:15 UTCGHSA enrichment
  25. 2026-10-01 19:56 UTCEG score recompute
Show 75 more
  1. 2026-10-01 19:56 UTCGHSA enrichment
  2. 2026-10-01 19:43 UTCEPSS rescore
  3. 2026-10-01 15:37 UTCGHSA enrichment
  4. 2026-10-01 11:18 UTCGHSA enrichment
  5. 2026-10-01 06:59 UTCGHSA enrichment
  6. 2026-10-01 02:40 UTCGHSA enrichment
  7. 2026-09-30 22:21 UTCGHSA enrichment
  8. 2026-09-30 18:01 UTCEG score recompute
  9. 2026-09-30 18:01 UTCGHSA enrichment
  10. 2026-09-30 14:58 UTCEPSS rescore
  11. 2026-09-30 13:32 UTCGHSA enrichment
  12. 2026-09-30 09:12 UTCGHSA enrichment
  13. 2026-09-30 04:54 UTCGHSA enrichment
  14. 2026-09-30 00:35 UTCGHSA enrichment
  15. 2026-09-29 20:13 UTCGHSA enrichment
  16. 2026-09-29 15:52 UTCEG score recompute
  17. 2026-09-29 15:52 UTCGHSA enrichment
  18. 2026-09-29 11:33 UTCGHSA enrichment
  19. 2026-09-29 07:14 UTCGHSA enrichment
  20. 2026-09-29 02:54 UTCGHSA enrichment
  21. 2026-09-28 22:34 UTCEG score recompute
  22. 2026-09-28 22:34 UTCGHSA enrichment
  23. 2026-09-28 18:15 UTCEG score recompute
  24. 2026-09-28 18:15 UTCGHSA enrichment
  25. 2026-09-28 13:45 UTCEPSS rescore
  26. 2026-09-28 13:35 UTCGHSA enrichment
  27. 2026-09-28 09:17 UTCGHSA enrichment
  28. 2026-09-28 04:58 UTCGHSA enrichment
  29. 2026-09-28 00:39 UTCGHSA enrichment
  30. 2026-09-27 20:20 UTCGHSA enrichment
  31. 2026-09-27 16:02 UTCEG score recompute
  32. 2026-09-27 16:01 UTCGHSA enrichment
  33. 2026-09-27 13:40 UTCEPSS rescore
  34. 2026-09-27 11:43 UTCGHSA enrichment
  35. 2026-09-27 07:22 UTCGHSA enrichment
  36. 2026-09-27 03:03 UTCGHSA enrichment
  37. 2026-09-26 22:43 UTCGHSA enrichment
  38. 2026-09-26 18:25 UTCEG score recompute
  39. 2026-09-26 18:25 UTCGHSA enrichment
  40. 2026-09-26 15:53 UTCEPSS rescore
  41. 2026-09-26 15:53 UTCEPSS rescore
  42. 2026-09-26 14:06 UTCGHSA enrichment
  43. 2026-09-26 09:47 UTCGHSA enrichment
  44. 2026-09-26 05:26 UTCGHSA enrichment
  45. 2026-09-26 01:03 UTCEG score recompute
  46. 2026-09-26 01:03 UTCGHSA enrichment
  47. 2026-09-25 20:41 UTCGHSA enrichment
  48. 2026-09-25 16:17 UTCGHSA enrichment
  49. 2026-09-25 11:58 UTCGHSA enrichment
  50. 2026-09-25 07:39 UTCGHSA enrichment
  51. 2026-09-25 03:20 UTCGHSA enrichment
  52. 2026-09-24 23:01 UTCGHSA enrichment
  53. 2026-09-24 18:42 UTCGHSA enrichment
  54. 2026-09-24 14:23 UTCEG score recompute
  55. 2026-09-24 14:23 UTCGHSA enrichment
  56. 2026-09-24 13:59 UTCEPSS rescore
  57. 2026-09-24 10:04 UTCGHSA enrichment
  58. 2026-09-24 05:45 UTCGHSA enrichment
  59. 2026-09-24 01:26 UTCGHSA enrichment
  60. 2026-09-23 21:08 UTCGHSA enrichment
  61. 2026-09-23 16:49 UTCEG score recompute
  62. 2026-09-23 16:49 UTCGHSA enrichment
  63. 2026-09-23 13:41 UTCEPSS rescore
  64. 2026-09-23 12:30 UTCGHSA enrichment
  65. 2026-09-23 08:11 UTCGHSA enrichment
  66. 2026-09-23 03:52 UTCGHSA enrichment
  67. 2026-09-22 23:33 UTCGHSA enrichment
  68. 2026-09-22 19:13 UTCEG score recompute
  69. 2026-09-22 19:13 UTCGHSA enrichment
  70. 2026-09-22 18:33 UTCGHSA enrichment
  71. 2026-09-22 17:37 UTCGHSA enrichment
  72. 2026-09-22 16:21 UTCGHSA enrichment
  73. 2026-09-22 15:30 UTCEG score recompute▲ 9.80
  74. 2026-09-22 15:30 UTCGHSA enrichment
  75. 2026-09-22 15:29 UTCMITRE cvelistV5CVSS v3 → 9.8 · severity → CRITICAL

Frequently asked(5)

What is CVE-2016-15059?
CVE-2016-15059 is a critical vulnerability published on September 22, 2026. Net::IDN::Punycode versions before 2.301 for Perl allow a heap buffer overflow via unchecked writes past the output buffer in encode_punycode. The XS backend builds the encoded label in the string buffer of the scalar it returns, sized from the input length. The loop that emits the digits of each…
When was CVE-2016-15059 disclosed?
CVE-2016-15059 was first published on September 22, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2016-15059 actively exploited?
CVE-2016-15059 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (33rd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2016-15059?
CVE-2016-15059 has a CVSS v3.1 base score of 9.8 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2016-15059?
No fix for CVE-2016-15059 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-2016-15059 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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