Medium severity · published Sep 1, 2026
CVE-2026-77950
RPC error handler fails open in AshTypescript, disclosing unredacted errors
6.3
CVSS
0.5%
EPSS
No
On KEV
Description
Generation of Error Message Containing Sensitive Information vulnerability in ash-project ash_typescript allows an unauthenticated attacker to receive unredacted internal error data by provoking an error shape the configured error handler does not match.
apply_error_handler/3 in lib/ash_typescript/rpc/errors.ex is the only hook an application has for redacting or suppressing errors before they reach the client, with a nil return dropping the error entirely. Its rescue clause logs a warning and then returns the original, pre-handler error map. Error handlers are conventionally written as pattern-matching functions over expected error shapes, so an unmatched shape raises FunctionClauseError and the raw transformed error, including any secrets carried in vars, is emitted instead. An intent to suppress an error becomes an intent to publish it. The rescue catches exceptions only, so a handler that throws or exits still propagates.
This issue affects ash_typescript: from 0.8.0 before 0.18.0.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 46% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
ash_typescript · ash-project
0.8.0 before 0.18.0; cb01cc8749e5a2a17fb45aedbe75df30a9f1126e before 59d8e985a98cf2e01794dbe5b919b897a95311f4 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-77950
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-77950
cna.erlef.org
https://cna.erlef.org/cves/CVE-2026-77950.html
github.com
https://github.com/ash-project/ash_typescript/commit/59d8e985a98cf2e01794dbe5b919b897a95311f4
github.com
https://github.com/ash-project/ash_typescript/security/advisories/GHSA-mjr7-r3rf-x963
osv.dev
https://osv.dev/vulnerability/EEF-CVE-2026-77950
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