AnyCable is a realtime server for reliable two-way communication that supports any backend. Prior to 1.6.15, the Pusher-compatible REST API in pusher/http.go includes the caller-supplied body_md5 value in the HMAC input but does not calculate the digest of the received request body or compare it with the signed value. An attacker who obtains a legitimate signed POST request can retain its query parameters and auth_signature while replacing the body, causing Handler and handleEvents to accept and broadcast attacker-selected event content. The absence of an auth_timestamp freshness check also allows the captured signature to be replayed indefinitely. This can forge server-side events, modify application state, or deliver attacker-controlled messages to WebSocket clients within the signed request's application context. This issue is fixed in version 1.6.15.
CVE-2026-63405
This medium-severity CVE scores 5.9 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 93% of all CVEs by exploit prediction. 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).
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 5.9
- EG Score
- 5.9(medium)
- EG Risk
- 43(Track)EG Risk 43/100SSVC: 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 computedSeverity59% × 45%Exploitation40% × 40%Automatability0% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 7%
- KEV
- Not listed
Published
September 18, 2026
Last Modified
September 18, 2026
Advisory Details (3)
Auto-updated Sep 18, 20261.6.15
Patch available: anycable/anycable v1.6.15
https://github.com/anycable/anycable/releases/tag/v1.6.15commit d2cbadec792f (anycable/anycable)
Fix landed in anycable/anycable commit d2cbadec792f — awaiting tagged release
https://github.com/anycable/anycable/commit/d2cbadec792f038f4695c84a65c0d957b0fde72cPusher REST API Does Not Verify Request Body MD5 Enabling Signed-Request Replay with Arbitrary Body · Advisory · anycable/anycable · GitHub
https://github.com/anycable/anycable/security/advisories/GHSA-5p54-whvp-x327Vendor Advisories for CVE-2026-63405(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 5× in last 7d / 5× 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.
- 2026-09-19 19:21 UTCEG score recompute
- 2026-09-18 18:27 UTCEG score recompute
- 2026-09-18 17:19 UTCEG score recompute
- 2026-09-18 16:54 UTCEG score recompute
- 2026-09-18 16:54 UTCMITRE cvelistV5first tracked
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Frequently asked(5)
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Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-63405
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