CVE-2026-48856
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedSensitive 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 OTP 17.0 before OTP 29.0.2, OTP 28.5.0.2 and OTP 27.3.4.13, corresponding to inets from 5.10 before 9.7.1, 9.6.2.2 and 9.3.2.6.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysisThe application redirects the browser to a URL taken from user input without validating it, so an attacker can craft a link on your trusted domain that quietly bounces victims to a malicious site. It is a staple of phishing and token theft. The fix is to allow-list redirect destinations or use indirect reference keys, never a raw user-supplied URL.
General guidance for the open redirect class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data>= 5.10, < 9.3.2.6>= 9.6, < 9.6.2.2>= 9.7, < 9.7.1>= 17.0, < 27.3.4.13>= 28.0, < 28.5.0.2>= 29.0, < 29.0.2CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped9.3.2.69.6.2.29.7.1
OTP 27.3.4.13+ (for 27.x), OTP 28.5.0.2+ (for 28.x), OTP 29.0.2+ (for 29.x); or inets 9.3.2.6+/9.6.2.2+/9.7.1+
- 1. Identify the current Erlang/OTP and inets version by running 'erl -eval 'erlang:display(erlang:system_info(otp_release)), halt().'' -noshell' or checking your deployment manifests
- 2. For Erlang/OTP >= 17.0 to < 27.3.4.13: Upgrade to OTP 27.3.4.13 or later
- 3. For Erlang/OTP >= 28.0 to < 28.5.0.2: Upgrade to OTP 28.5.0.2 or later
- 4. For Erlang/OTP >= 29.0 to < 29.0.2: Upgrade to OTP 29.0.2 or later
- 5. Alternatively, if using inets as a standalone component: upgrade to inets 9.3.2.6, 9.6.2.2, or 9.7.1 or later
- 6. After upgrade, verify the fix is applied by testing that httpc no longer forwards Authorization headers on cross-origin redirects
- 7. Review any custom httpc usage to ensure autoredirect behavior aligns with security expectations
Generated from the published advisory — verify against the referenced sources before acting.
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Free · runs locallyCheck whether your project pulls in CVE-2026-48856 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-48856 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
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