CVE-2026-91143

HIGHPre-NVD 7.27.2
EchelonGraph scoreMEDIUM confidence

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

Score 7.2 from GitHub Security Advisory (severity: MODERATE) published 2026-09-15. The CNA's CVSS baseline 7.2; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: the CNA's CVSS, EPSS, GitHub Security Advisory
Elevated

Also known asEUVD-2026-78166 (ENISA EUVD) · GHSA-pvfx-f5gx-wj35 (GitHub Security Advisories)Source: ENISA EUVD

7.2EG
EchelonGraph verdictPlan mitigationNo fix is confirmed yet: check the vendor's advisory for a fixed release; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 0.5%CVSS: 7.2Exploit: No code on recordExposed services: Not assessed

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

The CVE record's CNA (VulnCheck) lists snail007 goproxy versions up to and including 15.3 as affected. No release containing a fix is confirmed on record.

goproxy through 15.3 fails to apply HTTP proxy basic authentication to CONNECT tunnel requests, allowing unauthenticated clients to bypass credential requirements. Attackers can issue CONNECT requests to establish tunnels through the authenticated proxy without providing credentials, enabling arbitrary TCP traffic relay and access to restricted destinations.

CVSS v3
7.2
EG Score
7.2HIGHmedium confidence
EG Risk
63
EG Risk 63/100

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)
Severity72% × 45%
Impact severity (EG Severity): CVSS 7.2 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation public PoC (CISA Vulnrichment) · Automatable yes (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: No fix is confirmed yet. Check the vendor's advisory for a fixed release; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high.
EPSS PROB
0.5%
EPSS %ILE
40th
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 (7.2): severity, escalated by confirmed exploitation. This CVE's 7.2 is its impact severity (EG Severity), not escalated.

EG Severity
7.2 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.5% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-09). 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 low or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; 60 days if it is not.No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Attend at high (mission-essential systems).

No fix is confirmed yet. Check the vendor's advisory for a fixed release; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule at low or medium mission impact and sooner than that at high.

Exploitation public PoC (CISA Vulnrichment) · Automatable yes (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)14 days if the affected system is publicly exposed; 60 days if it is not.

No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable yes (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

September 14, 2026

Last Modified

September 24, 2026

Advisory Details (5)

Auto-updated Sep 14, 2026
No fix on record yet.
Web page

goproxy through 15.3 Authentication Bypass via CONNECT | Advisories | VulnCheck

https://www.vulncheck.com/advisories/goproxy-through-15.3-authentication-bypass-via-connect
Web page

GitHub - snail007/goproxy: 🔥 Proxy is a high performance HTTP(S) proxies, SOCKS5 proxies,WEBSOCKET, TCP, UDP proxy server implemented by golang. Now, it supports chain-style proxies,nat forwarding in different lan,TCP/UDP port forwarding, SSH forwarding.Proxy是golang实现的高性能http,https,websocket,tcp,socks5代理服务器,支持内网穿透,链式代理,通讯加密,智能HTTP,SOCKS5代理,黑白名单,限速,限流量,限连接数,跨平台,KCP支持,认证API。 · GitHub

https://github.com/snail007/goproxy
Web page

goproxy/services/http.go at v15.3 · snail007/goproxy · GitHub

https://github.com/snail007/goproxy/blob/v15.3/services/http.go
Web page

goproxy/utils/structs.go at v15.3 · snail007/goproxy · GitHub

https://github.com/snail007/goproxy/blob/v15.3/utils/structs.go
Web page

oss/goproxy.md at main · geo-chen/oss · GitHub

https://github.com/geo-chen/oss/blob/main/goproxy.md

Vendor Advisories for CVE-2026-91143(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 8× in last 7d / 34× 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 its CVE.org record (CNA or CISA ADP). 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). "EchelonGraph re-scored" is our own recompute of this CVE's score, not an update from a source, and is not counted in the refreshes above. Most recent first.

Showing the most recent 100 of 157 rows 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 57 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-12 16:35 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  2. 2026-11-11 16:41 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  3. 2026-11-10 16:46 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  4. 2026-11-10 02:48 UTCEchelonGraph re-scored
  5. 2026-11-10 02:48 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub severity MODERATE · GitHub CVSS 7.2
  6. 2026-11-09 16:36 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  7. 2026-11-08 16:41 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  8. 2026-11-07 16:40 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  9. 2026-11-06 16:39 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  10. 2026-11-05 16:39 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  11. 2026-11-04 16:37 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  12. 2026-11-03 17:04 UTCEchelonGraph re-scored
  13. 2026-11-03 17:04 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub severity MODERATE · GitHub CVSS 7.2
  14. 2026-11-03 16:49 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  15. 2026-11-02 16:46 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  16. 2026-11-01 16:36 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  17. 2026-10-30 16:35 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  18. 2026-10-29 16:34 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  19. 2026-10-28 16:33 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  20. 2026-10-28 05:28 UTCEchelonGraph re-scored
  21. 2026-10-28 05:28 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  22. 2026-10-27 16:33 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  23. 2026-10-26 16:32 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  24. 2026-10-25 16:34 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  25. 2026-10-25 13:51 UTCEchelonGraph re-scored
Show 75 more
  1. 2026-10-24 16:34 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  2. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  3. 2026-10-22 16:35 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  4. 2026-10-21 16:34 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  5. 2026-10-21 10:19 UTCEchelonGraph re-scored
  6. 2026-10-21 10:18 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  7. 2026-10-20 16:34 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  8. 2026-10-19 16:33 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  9. 2026-10-18 16:33 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  10. 2026-10-18 03:00 UTCEchelonGraph re-scored
  11. 2026-10-17 16:35 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  12. 2026-10-16 16:45 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  13. 2026-10-15 16:33 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  14. 2026-10-15 00:34 UTCEchelonGraph re-scored
  15. 2026-10-15 00:34 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  16. 2026-10-14 16:34 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  17. 2026-10-13 16:35 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  18. 2026-10-13 04:42 UTCEchelonGraph re-scored
  19. 2026-10-13 04:42 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  20. 2026-10-12 16:35 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  21. 2026-10-12 14:46 UTCEchelonGraph re-scored
  22. 2026-10-11 19:36 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  23. 2026-10-11 19:13 UTCEchelonGraph re-scored
  24. 2026-10-11 16:30 UTCEchelonGraph re-scored
  25. 2026-10-11 13:50 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  26. 2026-10-11 13:44 UTCEchelonGraph re-scored
  27. 2026-10-11 05:50 UTCEchelonGraph re-scored
  28. 2026-10-11 05:49 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  29. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  30. 2026-10-10 16:19 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  31. 2026-10-10 04:12 UTCEchelonGraph re-scored
  32. 2026-10-10 04:12 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  33. 2026-10-09 20:08 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  34. 2026-10-09 16:00 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  35. 2026-10-08 22:44 UTCEchelonGraph re-scored
  36. 2026-10-08 22:44 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  37. 2026-10-08 17:14 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  38. 2026-10-08 07:58 UTCEchelonGraph re-scored
  39. 2026-10-08 07:58 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  40. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  41. 2026-10-07 19:52 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  42. 2026-10-07 07:46 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  43. 2026-10-06 19:40 UTCEchelonGraph re-scored
  44. 2026-10-06 19:40 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  45. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  46. 2026-10-06 07:34 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  47. 2026-10-05 19:28 UTCEchelonGraph re-scored
  48. 2026-10-05 19:28 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  49. 2026-10-05 17:44 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  50. 2026-10-05 07:22 UTCEchelonGraph re-scored
  51. 2026-10-05 07:22 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  52. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  53. 2026-10-04 19:16 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  54. 2026-10-04 06:58 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  55. 2026-10-03 18:52 UTCEchelonGraph re-scored
  56. 2026-10-03 18:52 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  57. 2026-10-03 05:56 UTCEchelonGraph re-scored
  58. 2026-10-03 05:56 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  59. 2026-10-02 17:50 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  60. 2026-10-02 05:44 UTCEchelonGraph re-scored
  61. 2026-10-02 05:44 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  62. 2026-10-01 19:51 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  63. 2026-10-01 17:23 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  64. 2026-10-01 05:17 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  65. 2026-09-30 17:11 UTCEchelonGraph re-scored
  66. 2026-09-30 17:11 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  67. 2026-09-30 15:04 UTCEPSS rescoreEPSS 0.5% · 37th percentile
  68. 2026-09-30 05:02 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  69. 2026-09-29 16:56 UTCEchelonGraph re-scored
  70. 2026-09-29 16:56 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  71. 2026-09-29 04:18 UTCEchelonGraph re-scored
  72. 2026-09-29 04:18 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  73. 2026-09-28 16:12 UTCEchelonGraph re-scored
  74. 2026-09-28 16:12 UTCGHSA enrichmentGHSA-pvfx-f5gx-wj35 · GitHub CVSS 7.2
  75. 2026-09-28 13:52 UTCEPSS rescoreEPSS 0.5% · 37th percentile

Frequently asked(5)

What is CVE-2026-91143?
CVE-2026-91143 is a high-severity vulnerability; its CVE record was published on September 14, 2026. goproxy through 15.3 fails to apply HTTP proxy basic authentication to CONNECT tunnel requests, allowing unauthenticated clients to bypass credential requirements. Attackers can issue CONNECT requests to establish tunnels through the authenticated proxy without providing credentials, enabling…
When was CVE-2026-91143 made public?
CVE-2026-91143 was made public on July 29, 2026: that is the date its CVE record's CNA, VulnCheck, gives for when the vulnerability was made public. The CVE record itself was published on September 14, 2026. EchelonGraph's copy of the record carries a last-modified date of September 24, 2026; the record at its source may have been updated since.
Is CVE-2026-91143 actively exploited?
CVE-2026-91143 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.5% probability of exploitation in the next 30 days (40th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-91143?
CVE-2026-91143 has a CVSS base score of 7.2 (the CNA's own assessment, by vulncheck; NVD's own analysis pending).
How do I remediate CVE-2026-91143?
No fix for CVE-2026-91143 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 CVE record's CNA (VulnCheck) lists snail007 goproxy versions up to and including 15.3 as affected. No release containing a fix is confirmed on record. The vendor advisories EchelonGraph has for CVE-2026-91143 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-91143

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