CVE-2026-8836

CRITICALNVD 9.89.8
EchelonGraph scoreMEDIUM confidence

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

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-05-18. NVD baseline CVSS 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3

Also known asEUVD-2026-30793 (ENISA EUVD) · GHSA-3w8m-3w76-f6mh (GitHub Security Advisories)Source: ENISA EUVD

9.8EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1.1%CVSS: 9.8Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

A vulnerability was found in lwIP up to 2.2.1. Affected is the function snmp_parse_inbound_frame of the file src/apps/snmp/snmp_msg.c of the component snmpv3 USM Handler. Performing a manipulation of the argument msgAuthenticationParameters results in stack-based buffer overflow. The attack may be initiated remotely. The patch is named 0c957ec03054eb6c8205e9c9d1d05d90ada3898c. It is suggested to install a patch to address this issue. Two separate issue reports were submitted to the project. Their processing was merged as a duplicate.

CVSS v3
9.8
EG Score
9.8CRITICALmedium confidence
EG Risk
60
EG Risk 60/100

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)
Severity98% × 45%
Impact severity (EG Severity): CVSS 9.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation1.1% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
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 none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (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 available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
1.1%
EPSS %ILE
66th
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 (9.8): severity, escalated by confirmed exploitation. This CVE's 9.8 is its impact severity (EG Severity), not escalated.

EG Severity
9.8 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
1.1% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-11). 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: 3 days if the affected system is publicly exposed; 60 days if it is not.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).

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (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)3 days if the affected system is publicly exposed; 60 days if it is not.

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

May 18, 2026

Last Modified

August 22, 2026

Advisory Details (2)

Auto-updated Oct 31, 2026
Patch available. Sources: github_commit.
GitHub commit

commit 0c957ec03054 (lwip-tcpip/lwip)

Fix landed in lwip-tcpip/lwip commit 0c957ec03054 — awaiting tagged release

https://github.com/lwip-tcpip/lwip/commit/0c957ec03054eb6c8205e9c9d1d05d90ada3898c
Web page

snmpv3: fix handling packets with invalid msgAuthenticationParameters length - lwip.git - lwIP - A Lightweight TCPIP stack

https://cgit.git.savannah.gnu.org/cgit/lwip.git/commit/?id=0c957ec03054eb6c8205e9c9d1d05d90ada3898c

Vendor Advisories for CVE-2026-8836(1)

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

Patch Availability(1)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntuliblwip0t64 (2.2.1+dfsg1-4ubuntu0.1~esm1) @ resolute2026-11-02ubuntu

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

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
lwip2.1.2+dfsg1-8 ... 2.2.1+dfsg1-6 (24 versions)
  • every version on: no fix on record
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
lwip2.1.3+dfsg1-2 ... 2.2.1+dfsg1-7 (21 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
lwip2.2.1+dfsg1-1
  • every version up to 2.2.1+dfsg1-1+deb13u1: fixed in 2.2.1+dfsg1-1+deb13u1
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
lwip2.2.1+dfsg1-1, 2.2.1+dfsg1-2, 2.2.1+dfsg1-3, 2.2.1+dfsg1-4
  • every version up to 2.2.1+dfsg1-5: fixed in 2.2.1+dfsg1-5
—

Weakness Classification(2)

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 14× in last 7d / 69× 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 573 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 473 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 1.1% · 66th percentile
  2. 2026-11-12 15:20 UTCEchelonGraph re-scored
  3. 2026-11-12 15:20 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  4. 2026-11-11 16:41 UTCEPSS rescoreEPSS 1.1% · 66th percentile
  5. 2026-11-11 13:19 UTCEchelonGraph re-scored
  6. 2026-11-11 13:18 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  7. 2026-11-10 16:46 UTCEPSS rescoreEPSS 1.1% · 65th percentile
  8. 2026-11-10 11:14 UTCEchelonGraph re-scored
  9. 2026-11-10 11:14 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  10. 2026-11-09 16:36 UTCEPSS rescoreEPSS 1.1% · 65th percentile
  11. 2026-11-09 09:12 UTCEchelonGraph re-scored
  12. 2026-11-09 09:12 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  13. 2026-11-08 16:41 UTCEPSS rescoreEPSS 1.1% · 65th percentile
  14. 2026-11-08 07:11 UTCEchelonGraph re-scored
  15. 2026-11-08 07:11 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  16. 2026-11-07 16:40 UTCEPSS rescoreEPSS 1.1% · 65th percentile
  17. 2026-11-07 05:03 UTCEchelonGraph re-scored
  18. 2026-11-07 05:03 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  19. 2026-11-06 20:55 UTCOSV refresh
  20. 2026-11-06 16:39 UTCEPSS rescoreEPSS 1.1% · 65th percentile
  21. 2026-11-06 03:01 UTCEchelonGraph re-scored
  22. 2026-11-06 03:01 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  23. 2026-11-05 16:39 UTCEPSS rescoreEPSS 1.1% · 65th percentile
  24. 2026-11-05 00:59 UTCEchelonGraph re-scored
  25. 2026-11-05 00:59 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
Show 75 more
  1. 2026-11-04 16:37 UTCEPSS rescoreEPSS 1.1% · 65th percentile
  2. 2026-11-03 22:57 UTCEchelonGraph re-scored
  3. 2026-11-03 22:57 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  4. 2026-11-03 16:49 UTCEPSS rescoreEPSS 1.1% · 65th percentile
  5. 2026-11-02 20:56 UTCEchelonGraph re-scored
  6. 2026-11-02 20:56 UTCVendor advisory
  7. 2026-11-02 20:56 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  8. 2026-11-02 16:46 UTCEPSS rescoreEPSS 1.1% · 65th percentile
  9. 2026-11-01 18:53 UTCEchelonGraph re-scored
  10. 2026-11-01 18:53 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  11. 2026-10-31 16:52 UTCEchelonGraph re-scored
  12. 2026-10-31 16:52 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  13. 2026-10-31 16:33 UTCEPSS rescoreEPSS 1.1% · 65th percentile
  14. 2026-10-30 16:35 UTCEPSS rescoreEPSS 1.1% · 65th percentile
  15. 2026-10-30 14:31 UTCEchelonGraph re-scored
  16. 2026-10-30 14:31 UTCVendor advisory
  17. 2026-10-30 14:31 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  18. 2026-10-29 16:34 UTCEPSS rescoreEPSS 1.1% · 65th percentile
  19. 2026-10-29 12:29 UTCEchelonGraph re-scored
  20. 2026-10-29 12:29 UTCVendor advisory
  21. 2026-10-29 12:29 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  22. 2026-10-28 16:33 UTCEPSS rescoreEPSS 1.1% · 65th percentile
  23. 2026-10-28 10:21 UTCEchelonGraph re-scored
  24. 2026-10-28 10:21 UTCVendor advisory
  25. 2026-10-28 10:20 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  26. 2026-10-27 16:32 UTCEPSS rescoreEPSS 1.1% · 65th percentile
  27. 2026-10-27 07:23 UTCEchelonGraph re-scored
  28. 2026-10-27 07:23 UTCVendor advisory
  29. 2026-10-27 07:22 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  30. 2026-10-26 16:32 UTCEPSS rescoreEPSS 1.1% · 65th percentile
  31. 2026-10-26 02:23 UTCEchelonGraph re-scored
  32. 2026-10-26 02:23 UTCVendor advisory
  33. 2026-10-26 02:23 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  34. 2026-10-25 16:34 UTCEPSS rescoreEPSS 1.1% · 65th percentile
  35. 2026-10-25 13:53 UTCEchelonGraph re-scored
  36. 2026-10-25 00:21 UTCEchelonGraph re-scored
  37. 2026-10-25 00:21 UTCVendor advisory
  38. 2026-10-25 00:21 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  39. 2026-10-24 16:34 UTCEPSS rescoreEPSS 1.6% · 75th percentile
  40. 2026-10-23 22:19 UTCEchelonGraph re-scored
  41. 2026-10-23 22:19 UTCVendor advisory
  42. 2026-10-23 22:19 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  43. 2026-10-23 16:32 UTCEPSS rescoreEPSS 1.6% · 75th percentile
  44. 2026-10-22 20:17 UTCEchelonGraph re-scored
  45. 2026-10-22 20:16 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  46. 2026-10-22 16:35 UTCEPSS rescoreEPSS 1.6% · 74th percentile
  47. 2026-10-21 18:13 UTCEchelonGraph re-scored
  48. 2026-10-21 18:13 UTCVendor advisory
  49. 2026-10-21 18:12 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  50. 2026-10-21 16:34 UTCEPSS rescoreEPSS 1.6% · 74th percentile
  51. 2026-10-20 16:34 UTCEPSS rescoreEPSS 1.6% · 74th percentile
  52. 2026-10-20 16:09 UTCEchelonGraph re-scored
  53. 2026-10-20 16:09 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  54. 2026-10-19 16:33 UTCEPSS rescoreEPSS 1.6% · 74th percentile
  55. 2026-10-19 14:01 UTCEchelonGraph re-scored
  56. 2026-10-19 14:00 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  57. 2026-10-18 16:33 UTCEPSS rescoreEPSS 1.6% · 74th percentile
  58. 2026-10-18 11:56 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  59. 2026-10-18 03:03 UTCEchelonGraph re-scored
  60. 2026-10-17 16:35 UTCEPSS rescoreEPSS 1.6% · 74th percentile
  61. 2026-10-17 09:54 UTCEchelonGraph re-scored
  62. 2026-10-17 09:54 UTCVendor advisory
  63. 2026-10-17 09:54 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  64. 2026-10-16 16:44 UTCEPSS rescoreEPSS 1.6% · 74th percentile
  65. 2026-10-16 07:51 UTCEchelonGraph re-scored
  66. 2026-10-16 07:51 UTCVendor advisory
  67. 2026-10-16 07:51 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  68. 2026-10-15 16:33 UTCEPSS rescoreEPSS 1.6% · 74th percentile
  69. 2026-10-15 05:48 UTCEchelonGraph re-scored
  70. 2026-10-15 05:48 UTCVendor advisory
  71. 2026-10-15 05:48 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  72. 2026-10-14 16:34 UTCEPSS rescoreEPSS 1.6% · 74th percentile
  73. 2026-10-14 01:26 UTCEchelonGraph re-scored
  74. 2026-10-14 01:25 UTCGHSA enrichmentGHSA-3w8m-3w76-f6mh · GitHub severity CRITICAL · GitHub CVSS 9.8
  75. 2026-10-13 16:35 UTCEPSS rescoreEPSS 1.6% · 74th percentile

Frequently asked(5)

What is CVE-2026-8836?
CVE-2026-8836 is a critical-severity vulnerability; its CVE record was published on May 18, 2026. A vulnerability was found in lwIP up to 2.2.1. Affected is the function snmp_parse_inbound_frame of the file src/apps/snmp/snmp_msg.c of the component snmpv3 USM Handler. Performing a manipulation of the argument msgAuthenticationParameters results in stack-based buffer overflow. The attack may be…
When was the CVE record for CVE-2026-8836 published?
The CVE record for CVE-2026-8836 was published on May 18, 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 22, 2026; the record at its source may have been updated since.
Is CVE-2026-8836 actively exploited?
CVE-2026-8836 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1.1% probability of exploitation in the next 30 days (66th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-8836?
CVE-2026-8836 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2026-8836?
A fix for CVE-2026-8836 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-8836 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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