Cyber Resilience

CVE-2026-54891

Erlang\/Otp 17.0 – 27.3.4.14

Published
02 July 2026
Modified
26 August 2026
Patch / advisory
CVSS Score v4 6.3
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0014 3th percentile
Risk Priority 29 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-54891 is a medium-severity Improper Enforcement of Message Integrity During Transmission in a Communication Channel (CWE-924) vulnerability in Erlang Erlang\/Otp. Its CVSS base score is 6.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Adversary-in-the-Middle (T1557); ranked at the 3th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SC-8 (Transmission Confidentiality and Integrity) and SC-16 (Transmission of Security and Privacy Attributes) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

Improper Enforcement of Message Integrity During Transmission in a Communication Channel vulnerability in Erlang/OTP ssl (tls_gen_connection module) allows a network-positioned attacker to inject unauthenticated plaintext that the TLS client application later treats as authenticated server data. The function tls_gen_connection:handle_protocol_record/3 rejects…

more

APPLICATION_DATA records that arrive in pre-handshake states when the TLS endpoint acts as a server, but does not apply the same check when the endpoint acts as a client. A network-positioned attacker can send plaintext APPLICATION_DATA records to the client during the handshake. The records are buffered and, once the handshake completes successfully, delivered to the application as if they were authenticated post-handshake data. The attacker cannot observe the client's response or steer the connection, so the impact is limited to blind injection of unauthenticated bytes. The injection window is wider for TLS versions prior to TLS 1.3 than for TLS 1.3. This vulnerability is associated with program file lib/ssl/src/tls_gen_connection.erl. TLS 1.3 is affected starting with OTP 22.0, when TLS 1.3 support was added. This issue affects OTP from OTP 17.0 before OTP 27.3.4.14, from OTP 28.0 before OTP 28.5.0.3, and from OTP 29.0 before OTP 29.0.3, corresponding to ssl from 5.3.4 before 11.2.12.10, from 11.3 before 11.6.0.3, and from 11.7 before 11.7.3. Whether OTP before OTP 17.0, corresponding to ssl before 5.3.4, is affected is unknown.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1557 Adversary-in-the-Middle Credential Access
Adversaries may attempt to position themselves between two or more networked devices using an adversary-in-the-middle (AiTM) technique to support follow-on behaviors such as [Network Sniffing](https://attack.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-58227Same product: Erlang Erlang\/Otp
CVE-2026-48860Same product: Erlang Erlang\/Otp
CVE-2026-54887Same product: Erlang Erlang\/Otp
CVE-2026-55953Same product: Erlang Erlang\/Otp
CVE-2026-55950Same product: Erlang Erlang\/Otp
CVE-2026-55952Same product: Erlang Erlang\/Otp
CVE-2026-32144Same product: Erlang Erlang\/Otp
CVE-2026-42790Same product: Erlang Erlang\/Otp
CVE-2026-42789Same product: Erlang Erlang\/Otp
CVE-2026-42791Same product: Erlang Erlang\/Otp

Affected Assets

erlang
erlang\/otp
17.0 — 27.3.4.14 · 28.0 — 28.5.0.3 · 29.0 — 29.0.3
erlang
erlang\/ssl
5.3.4 — 11.2.12.10 · 11.3 — 11.6.0.3 · 11.7 — 11.7.3

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 6 hardening rules · 1 OS baseline
Validate
Prove the fix (OWASP ASVS)

—

Mitigating Controls (NIST 800-53 r5) AI

Requires protection of integrity for transmitted information, directly stopping the failure to verify messages were unmodified in transit.

Associates integrity-related security attributes with exchanged information, helping ensure modification can be detected during transmission.

Protects session authenticity, which structurally reduces the ability to undetectably modify messages in the channel.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.DS-02 full match
prevents

Directly requires integrity protection (e.g., signatures/hashes) for data-in-transit, which prevents the described weakness while also addressing confidentiality/availability.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Mandates network security controls that can enforce message integrity on channels.

prevents

Addresses security of network services, which may include integrity mechanisms.

prevents

Cryptography is the primary technical means to enforce message integrity during transmission.

prevents

Requires secure information transfer procedures that can include integrity checks.

prevents

Application security requirements can specify integrity protection for transmitted messages.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (4 rules)
  • V-248574 YUM must be configured to prevent the installation of patches, service packs, device drivers, or OL 8 system components that have not been digitally signed using a certificate that is recognized and approved by the organization. prevents CWE-924
  • V-248823 OL 8 must not have the telnet-server package installed. prevents CWE-924
  • V-248827 OL 8 must not have the rsh-server package installed. prevents CWE-924

References