Plaintext APPLICATION_DATA injected during TLS handshake delivered to client application post-handshake in ssl
Summary
| CVE | CVE-2026-54891 |
|---|---|
| State | PUBLISHED |
| Assigner | EEF |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-07-02 17:17:02 UTC |
| Updated | 2026-08-03 16:16:29 UTC |
| Description | 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 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 R13B03 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 3.10.7 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 R13B03, corresponding to ssl before 3.10.7, is affected is unknown. |
Risk And Classification
Primary CVSS: v4.0 6.3 MEDIUM from 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
CVSS: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: 0.001640000 probability, percentile 0.059280000 (date 2026-07-05)
Problem Types: CWE-924 | CWE-924 CWE-924 Improper Enforcement of Message Integrity During Transmission in a Communication Channel
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | Secondary | 6.3 | MEDIUM | CVSS: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/C... |
| 4.0 | CNA | CVSS | 6.3 | MEDIUM | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N |
| 3.1 | [email protected] | Primary | 3.7 | LOW | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N |
CVSS v4.0 Breakdown
CVSS: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
CVSS v3.1 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Application | Erlang | Erlang/otp | All | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Erlang | OTP | unknown R13B03 otp | Not specified |
| CNA | Erlang | OTP | affected R13B03 27.3.4.14 otp | Not specified |
| CNA | Erlang | OTP | affected 28.0 28.5.0.3 otp | Not specified |
| CNA | Erlang | OTP | affected 29.0 29.0.3 otp | Not specified |
| CNA | Erlang | OTP | unknown 3.10.7 otp | Not specified |
| CNA | Erlang | OTP | affected 3.10.7 11.2.12.10 otp | Not specified |
| CNA | Erlang | OTP | affected 11.3 11.6.0.3 otp | Not specified |
| CNA | Erlang | OTP | affected 11.7 11.7.3 otp | Not specified |
| CNA | Erlang | OTP | affected 84adefa331c4159d432d22840663c38f155cd4c1 07d2d0e93f6aaf7652a81e8df075fc1728da5e96 git | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/erlang/otp/security/advisories/GHSA-gf6r-99xw-6qg6 | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | github.com | Vendor Advisory |
| www.erlang.org/doc/system/versions.html | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | www.erlang.org | Release Notes |
| github.com/erlang/otp/commit/07d2d0e93f6aaf7652a81e8df075fc1728da5e96 | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | github.com | Patch |
| osv.dev/vulnerability/EEF-CVE-2026-54891 | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | osv.dev | Third Party Advisory |
| cna.erlef.org/cves/CVE-2026-54891.html | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | cna.erlef.org | Vendor Advisory |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Lukas Backström (en)
CNA: Ingela Anderton Andin (en)
CNA: Dan Gudmundsson (en)
CNA: Jakub Witczak (en)