CVE-2026-72861

MEDIUMPre-NVD 5.85.8
EchelonGraph scoreLOW confidence

This medium-severity CVE scores 5.8 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit-prediction score not yet available (the EPSS model rescores nightly; freshly-published CVEs typically appear within 48 hours). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: secondary
5.8EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: —CVSS: 5.8Exploit: None knownExposed: 0

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

The github-issue-bot templates in appwrite/templates verify the GitHub webhook signature with an inverted condition. verifyWebhook in node/github-issue-bot/src/github.js and in node-typescript/github-issue-bot/src/github.ts returns "typeof signature !== 'string' || (await verify(...))", so when the X-Hub-Signature-256 header is absent the first operand is true, the logical OR short-circuits, and the function reports success without performing any HMAC verification. main.js rejects a request only when verifyWebhook returns false, so an unauthenticated request carrying no signature passes the check. Processing then continues to postComment, which takes the repository and issue objects directly from the request body, letting the caller direct the deployed function to post a comment on a repository and issue of their choosing using the configured GITHUB_TOKEN, with the issue author login from the body interpolated into the comment text.

CVSS v3
5.8
EG Score
5.8(low)
EG Risk
31(Track)
EG Risk 31/100SSVC: Track

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
Severity58% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
—
EPSS %ILE
—
KEV
Not listed

Published

August 20, 2026

Last Modified

August 20, 2026

Advisory Details (6)

Auto-updated Aug 20, 2026
No patch confirmed yet.
generic

Appwrite Templates github-issue-bot Skips Webhook Signature Verification When the X-Hub-Signature-256 Header Is Absent | Advisories | VulnCheck

https://www.vulncheck.com/advisories/appwrite-templates-github-issue-bot-skips-webhook-signature-verification-when-the-x-hub-signature-256-header-is-absent
generic

GitHub - appwrite/templates: Templates for Appwrite Functions ⚡️🌩️ · GitHub

https://github.com/appwrite/templates
generic

templates/node/github-issue-bot/src/main.js at 1.1.2 · appwrite/templates · GitHub

https://github.com/appwrite/templates/blob/1.1.2/node/github-issue-bot/src/main.js
generic

templates/node-typescript/github-issue-bot/src/github.ts at 1.1.2 · appwrite/templates · GitHub

https://github.com/appwrite/templates/blob/1.1.2/node-typescript/github-issue-bot/src/github.ts
generic

templates/node/github-issue-bot/src/github.js at 1.1.2 · appwrite/templates · GitHub

https://github.com/appwrite/templates/blob/1.1.2/node/github-issue-bot/src/github.js
generic

Authentication Bypass in GitHub Webhook Verification via Missing X-Hub-Signature-256 Header · Issue #350 · appwrite/templates · GitHub

https://github.com/appwrite/templates/issues/350

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 3× in last 7d / 3× 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. 2026-08-20 20:20 UTCEG score recompute
  2. 2026-08-20 19:52 UTCEG score recompute
  3. 2026-08-20 19:51 UTCMITRE cvelistV5first tracked

Frequently asked(4)

What is CVE-2026-72861?
CVE-2026-72861 is a medium vulnerability published on August 20, 2026. The github-issue-bot templates in appwrite/templates verify the GitHub webhook signature with an inverted condition. verifyWebhook in node/github-issue-bot/src/github.js and in node-typescript/github-issue-bot/src/github.ts returns "typeof signature !== 'string' || (await verify(...))", so when the…
When was CVE-2026-72861 disclosed?
CVE-2026-72861 was first published in the National Vulnerability Database on August 20, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
What is the CVSS score of CVE-2026-72861?
CVE-2026-72861 has a CVSS v3 base score of 5.8 (NVD). The EG score is currently aggregating — additional source signals are being incorporated as they become available..
How do I remediate CVE-2026-72861?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-72861, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-72861

Explore →

Is Your Infrastructure Affected by CVE-2026-72861?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs