CVE-2026-16599

MEDIUMPre-NVD 5.15.1
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

This medium-severity CVE scores 5.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4% (31st percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from a secondary CVSS source
Sources: EPSS, a secondary CVSS source
Trending — 3 sources updated this week

Also known asEUVD-2026-65494 (ENISA EUVD) · GHSA-48r3-mr49-jp8x (GitHub Security Advisories)Source: ENISA EUVD

5.1EG
EchelonGraph verdictMonitorRemediate within your standard update timelines (the SSVC decision on this page).
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 5.1Exploit: None knownExposed services: Not assessed

A fix is referenced (a reference tagged "Patch", often a source commit), but no release containing it is confirmed — find the release that contains it; until it is applied, mitigate (WAF / firewall / segmentation).

GNU wget is vulnerable to denial of service in its FTP OPIE/S-KEY authentication functionality. The server-supplied sequence number from the FTP challenge line is used as an iteration count for an MD5 key-derivation loop without any upper bound validation. A malicious FTP server or a network attacker positioned to intercept FTP traffic can send a crafted OPIE challenge with a sequence number near INT_MAX, causing wget to perform up to approximately 2.1 billion MD5 computations and suspend for some time. The --timeout option does not mitigate this because it applies only to network I/O, not CPU computation.

This issue was fixed in commit e9697d98e7249b0f68a6be040a4f3dcc5bc101fa

CVSS v3
5.1
EG Score
5.1MEDIUMmedium confidence
EG Risk
23
EG Risk 23/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity51% × 45%
Impact severity (EG Severity): CVSS 5.1 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.4% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it and apply that within your standard update timelines; until then, restrict network exposure of the affected system or apply the vendor's mitigation.
EPSS PROB
0.4%
EPSS %ILE
31st
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (5.1): severity, escalated by confirmed exploitation. This CVE's 5.1 is its impact severity (EG Severity), not escalated.

EG Severity
5.1 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.a secondary CVSS source · CVSS v3.0 or v3.1
EG Likelihood
0.4% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-24). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.

A fix is referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it and apply that within your standard update timelines; until then, restrict network exposure of the affected system or apply the vendor's mitigation.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

August 25, 2026

Last Modified

August 28, 2026

Advisory Details (3)

Auto-updated Aug 25, 2026
Fix referenced — no release confirmed yet.
Web page

Fix server-controlled unbounded MD5 loop in FTP OPIE (e9697d98) · Commits · Wget / wget · GitLab

https://gitlab.com/gnuwget/wget/-/commit/e9697d98e7249b0f68a6be040a4f3dcc5bc101fa
Web page

Wget / wget · GitLab

https://gitlab.com/gnuwget/wget
Web page

Vulnerability in GNU wget software | CERT Polska

https://cert.pl/en/posts/2026/08/CVE-2026-16599

Vendor Advisories for CVE-2026-16599(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
wget1.21.3-1 ... 1.25.0-3 (8 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
wget1.25.0-2, 1.25.0-3
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
wget1.25.0-2, 1.25.0-3
  • 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 / 62× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 100 of 146 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 46 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  2. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  3. 2026-10-25 14:46 UTCEG score recompute
  4. 2026-10-24 16:32 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  5. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  6. 2026-10-23 06:19 UTCEG score recompute
  7. 2026-10-23 06:19 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  8. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  9. 2026-10-21 16:32 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  10. 2026-10-20 16:32 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  11. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  12. 2026-10-18 16:31 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  13. 2026-10-18 04:00 UTCEG score recompute
  14. 2026-10-17 16:33 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  15. 2026-10-16 16:40 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  16. 2026-10-15 16:31 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  17. 2026-10-14 16:32 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  18. 2026-10-13 16:33 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  19. 2026-10-12 16:33 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  20. 2026-10-12 16:30 UTCEG score recompute
  21. 2026-10-11 20:09 UTCEG score recompute
  22. 2026-10-11 17:21 UTCEG score recompute
  23. 2026-10-11 14:54 UTCEG score recompute
  24. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  25. 2026-10-10 19:59 UTCEPSS rescoreEPSS 0.4% · 29th percentile
Show 75 more
  1. 2026-10-10 12:06 UTCEG score recompute
  2. 2026-10-10 12:06 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  3. 2026-10-09 20:06 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  4. 2026-10-09 07:25 UTCEG score recompute
  5. 2026-10-09 07:25 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  6. 2026-10-08 17:11 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  7. 2026-10-08 07:04 UTCEG score recompute
  8. 2026-10-08 07:04 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  9. 2026-10-07 23:47 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  10. 2026-10-07 07:21 UTCEG score recompute
  11. 2026-10-07 07:21 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  12. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  13. 2026-10-06 07:43 UTCEG score recompute
  14. 2026-10-06 07:43 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  15. 2026-10-05 17:42 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  16. 2026-10-05 05:24 UTCEG score recompute
  17. 2026-10-05 05:24 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  18. 2026-10-04 23:21 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  19. 2026-10-04 05:47 UTCEG score recompute
  20. 2026-10-04 05:47 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  21. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  22. 2026-10-03 06:10 UTCEG score recompute
  23. 2026-10-03 06:10 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  24. 2026-10-02 06:28 UTCEG score recompute
  25. 2026-10-02 06:28 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  26. 2026-10-01 19:49 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  27. 2026-10-01 06:26 UTCEG score recompute
  28. 2026-10-01 06:26 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  29. 2026-09-30 15:02 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  30. 2026-09-30 06:49 UTCEG score recompute
  31. 2026-09-30 06:49 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  32. 2026-09-29 15:20 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  33. 2026-09-28 21:30 UTCEG score recompute
  34. 2026-09-28 21:30 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  35. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  36. 2026-09-27 21:45 UTCEG score recompute
  37. 2026-09-27 21:44 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  38. 2026-09-27 13:47 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  39. 2026-09-26 22:06 UTCEG score recompute
  40. 2026-09-26 22:06 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  41. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  42. 2026-09-24 22:15 UTCEG score recompute
  43. 2026-09-24 22:15 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  44. 2026-09-23 22:17 UTCEG score recompute
  45. 2026-09-23 22:17 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  46. 2026-09-22 22:40 UTCEG score recompute
  47. 2026-09-22 22:40 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  48. 2026-09-21 23:02 UTCEG score recompute
  49. 2026-09-21 23:02 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  50. 2026-09-20 23:25 UTCEG score recompute
  51. 2026-09-20 23:25 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  52. 2026-09-19 23:20 UTCEG score recompute
  53. 2026-09-19 23:20 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  54. 2026-09-18 23:42 UTCEG score recompute
  55. 2026-09-18 23:42 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  56. 2026-09-18 19:27 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  57. 2026-09-18 00:05 UTCEG score recompute
  58. 2026-09-18 00:05 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  59. 2026-09-16 23:13 UTCEG score recompute
  60. 2026-09-16 23:13 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  61. 2026-09-16 14:07 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  62. 2026-09-16 05:14 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  63. 2026-09-15 23:35 UTCEG score recompute
  64. 2026-09-15 23:35 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  65. 2026-09-14 23:43 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  66. 2026-09-13 23:23 UTCEG score recompute
  67. 2026-09-13 23:23 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  68. 2026-09-13 16:46 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  69. 2026-09-12 23:46 UTCEG score recompute
  70. 2026-09-12 23:46 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  71. 2026-09-12 15:00 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  72. 2026-09-12 00:09 UTCEG score recompute
  73. 2026-09-12 00:08 UTCGHSA enrichmentGHSA-48r3-mr49-jp8x
  74. 2026-09-11 14:52 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  75. 2026-09-11 09:36 UTCEPSS rescoreEPSS 0.4% · 31st percentile

Frequently asked(5)

What is CVE-2026-16599?
CVE-2026-16599 is a medium-severity vulnerability; its CVE record was published on August 25, 2026. GNU wget is vulnerable to denial of service in its FTP OPIE/S-KEY authentication functionality. The server-supplied sequence number from the FTP challenge line is used as an iteration count for an MD5 key-derivation loop without any upper bound validation. A malicious FTP server or a network…
When was the CVE record for CVE-2026-16599 published?
The CVE record for CVE-2026-16599 was published on August 25, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of August 28, 2026; the record at its source may have been updated since.
Is CVE-2026-16599 actively exploited?
CVE-2026-16599 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (31st percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-16599?
CVE-2026-16599 has a CVSS base score of 5.1 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-16599?
A fix for CVE-2026-16599 is referenced (a reference tagged "Patch", often a source commit), but EchelonGraph has no release containing it on record. Check that reference and the vendor's advisory for a release that contains the fix and update to it; until then, restrict network exposure of the affected system or apply the vendor's mitigation. The vendor advisories EchelonGraph has for CVE-2026-16599 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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