Erlang\/otpApplication · Erlang

CVE-2026-48855

MEDIUM · 6.5 CVSS v3.1 Published 2026-06-10
Fix available
A fix is available. Upgrade to 5.2.11.8 / 5.5.2.1 or later.
See remediation →
71/100
Remediation priority · Elevated
Remotely reachable Zero-click Patch available

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 · unedited
Exposure of Sensitive Information to an Unauthorized Actor vulnerability in Erlang OTP ssh (ssh_sftpd module) allows File Discovery. The SSH_FXP_READLINK handler in ssh_sftpd sends the raw result of file:read_link/2 to the client without calling chroot_filename/2 to strip the backend root prefix. An authenticated SFTP client can create a symlink inside the chroot pointing to /; ssh_sftpd resolves the target to the absolute backend root and stores it on disk. Reading the symlink back via SSH_FXP_READLINK returns that absolute path, for example /data/sftp, instead of the chrooted value /. The information disclosed is the absolute filesystem path of the SFTP root directory and of any symlink targets within it. No file contents, credentials, or access to paths outside the root directory are obtainable through this issue alone. This vulnerability is associated with program files lib/ssh/src/ssh_sftpd.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 ssh from 3.0.1 before 6.0.1, 5.5.2.1 and 5.2.11.8.

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 analysis
How this class of weakness works · CWE-200

The application discloses data — error detail, internal paths, tokens, or other users' records — to someone who shouldn't see it. On its own it can look minor, but it hands attackers the map they need for a larger attack. Remediation is about minimising what's returned and enforcing authorization on every piece of data.

General guidance for the information exposure 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
Erlang\/otpApplication
Affected:>= 17.0, < 27.3.4.13>= 28.0, < 28.5.0.2>= 29.0, < 29.0.2
Erlang\/sshApplication
Affected:>= 3.0.1, < 5.2.11.8>= 5.5, < 5.5.2.1>= 6.0, < 6.0.1

CVSS 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 · scoped
Upgrade available Upgrade to 5.2.11.8 / 5.5.2.1 / 6.0.1 or later
Fixed in 5.2.11.85.5.2.16.0.1
Vendor patch github.com →
Recommended fix High confidence

OTP 27.3.4.13 (or later 27.x), OTP 28.5.0.2 (or later 28.x), or OTP 29.0.2 (or later 29.x) - choose the appropriate branch for your environment

  1. Identify your current Erlang/OTP version using 'erl -eval 'erlang:display(erlang:system_info(otp_release)), halt().' -noshell'
  2. If using OTP 27.x: upgrade to OTP 27.3.4.13 or later (e.g., 27.3.5)
  3. If using OTP 28.x: upgrade to OTP 28.5.0.2 or later (e.g., 28.5.1)
  4. If using OTP 29.x: upgrade to OTP 29.0.2 or later (e.g., 29.0.3)
  5. If using OTP 17.0 through 26.x: upgrade to OTP 27.3.4.13 or later as these versions are all affected
  6. After upgrade, verify the fix by confirming SSH_FXP_READLINK now returns chroot-relative paths instead of absolute backend paths
  7. Alternatively, apply vendor patch from commit 8f4224a0d2676b0653d2c71a889a956e8c2c62d6 to ssh_sftpd.erl
  8. Restart the SSH/SFTP service to load the patched or upgraded code
Caveat Major version upgrades (e.g., 27->28, 28->29) may introduce breaking changes; review OTP release notes before upgrading

Generated from the published advisory — verify against the referenced sources before acting.

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $900. Get the upgrade done

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-48855 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-48855 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data