Open Redirect in Erlangotp (CVE-2026-48856)
Summary
Vulnerability in Erlangotp (CVE-2026-48856). Confidential information can be exposed externally. Exploitable via Authorization header.
Original description
The description as published by the source.
Summary
Sensitive Data Exposure vulnerability in Erlang OTP inets (httpc_response module) allows Retrieve Embedded Sensitive Data.
The httpc client forwards the Authorization and Proxy-Authorization request headers to redirect targets without checking whether the redirect crosses an origin boundary. httpc_response:redirect/2 constructs the redirected request by updating only the host field of the header record; all other fields (including authorization and proxy_authorization) are copied verbatim. The redirect target host is never compared against the original host.
autoredirect defaults to true, so this affects all httpc callers that do not explicitly disable automatic redirects.
An attacker who controls a server that the victim contacts via httpc can issue a cross-origin 3xx redirect to a server they also control. The Authorization header (including Basic credentials derived from URL userinfo via httpc_request:handle_user_info/2) is forwarded to the redirect target, allowing credential theft. The same applies to the Proxy-Authorization header.
This vulnerability is associated with program files lib/inets/src/http_client/httpc_response.erl.
This issue affects OTP from 17.0 before 29.0.2, 28.5.0.2 and 27.3.4.13 corresponding to inets from 5.10 before 9.7.1, 9.6.2.2 and 9.3.2.6.
Workaround
* Set {autoredirect, false} in the httpc:request/4 options and handle redirects manually, stripping the Authorization header when the redirect crosses an origin bounda…
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-48856 has been found in Erlangotp.
Attackers can target a specific entry point like Authorization header over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 6.5/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Erlangotp CVE-2026-48856" on the vendor's site.
CVE-2026-48856 (Erlangotp) — CWE-601 / CVSS v3 6.5
Attack vector: remote (network-reachable) / no user interaction
Attack surface: Authorization header
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-601) exists in Erlangotp. Attackers reach the vulnerable code path via Authorization header.
Check the vendor advisory for the affected versions of Erlangotp. Attack surface: Authorization header.
Severity: Medium (CVSS 6.5/10). Confidential information can be exposed externally.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Erlangotp' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'Erlangotp' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
Erlangotpを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-48856 erlang
- Ubuntu UBUNTU-CVE-2026-48856 erlang Fixed in: 1:16.b.3-dfsg-1ubuntu2.2+esm3
References
- advisory cna.erlef.org
- advisory osv.dev
- patch github.com
- patch github.com
- web erlang.org
- web github.com