Weakness Type (CWE)

CWE-601 — CWE-601 URL Redirection to Untrusted Site ('Open Redirect')

CAPEC

CVSS 4.0 Score

7.1

HIGH

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

Vulnerability description

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.

Affected

pkg:otp/inets

Module Source File Routine
httpc_response src/http_client/httpc_response.erl httpc_response:redirect/2
Status Type Version Changes / Fixed in
affected otp ⓘ 5.10
  • unaffected at 9.7.1
  • unaffected at 9.6.2.2
  • unaffected at 9.3.2.6

pkg:github/erlang/otp

Module Source File Routine
httpc_response lib/inets/src/http_client/httpc_response.erl httpc_response:redirect/2
Status Type Version Changes / Fixed in
affected otp ⓘ 17.0
affected git ⓘ 84adefa331 < 688d748d6f

Workarounds

  • Set {autoredirect, false} in the httpc:request/4 options and handle redirects manually, stripping the Authorization header when the redirect crosses an origin boundary.
  • Ensure that httpc is only used to contact trusted servers that will not issue cross-origin redirects.

References

Credits

  • Finder: Jonatan Männchen / EEF
  • Remediation developer: Jonatan Männchen / EEF
  • Remediation reviewer: Ingela Anderton Andin
  • Remediation reviewer: Konrad Pietrzak

CVE record as JSON:  GET /cves/CVE-2026-48856.json
OSV record as JSON:  GET /osv/EEF-CVE-2026-48856.json