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CVE-2026-54887· NVD / CVE Program· CNA EEF

DTLS server cookie bypass during startup window due to empty initial cookie secret

Noroxi assessment

Priority: Monitor (action score 25/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.24% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Erlang OTP 11.2.12.10, 11.6.0.3, 11.7.3; azl3 erlang 26.2.5.21-4 on Azure Linux 3.0 26.2.5.21-5.

Low priority for now. Upgrade to Erlang OTP 11.2.12.10, 11.6.0.3, 11.7.3; azl3 erlang 26.2.5.21-4 on Azure Linux 3.0 26.2.5.21-5 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Use of Default Cryptographic Key vulnerability in Erlang/OTP ssl (DTLS server) allows predictable DTLS cookie computation during the startup window, enabling source address verification bypass. On DTLS server startup, dtls_server_connection:initial_hello/3 initializes previous_cookie_secret to the empty binary (<<>>) instead of a random value. Because HMAC with an empty key is deterministic, anyone who observes the plaintext ClientHello can compute dtls_handshake:cookie(<<>>, IP, Port, Hello) and forge a valid DTLS cookie before the first rotation of the cookie secret. The DTLS cookie (RFC 6347 §4.2.1) is a denial-of-service mitigation that prevents spoofed source IPs from forcing the server to allocate state and perform expensive cryptographic operations; it is not an authentication mechanism. During the window from server startup until the first secret rotation (0 to 15 seconds), an attacker who can observe the plaintext ClientHello can bypass the source address verification, enabling DTLS handshake amplification with spoofed source addresses. This vulnerability is associated with program file lib/ssl/src/dtls_server_connection.erl and program routine dtls_server_connection:initial_hello/3. This issue affects OTP from OTP 20.0 before OTP 29.0.3, OTP 28.5.0.3 and OTP 27.3.4.14, corresponding to ssl from 8.2 before 11.7.3, 11.6.0.3 and 11.2.12.10.

MediumCVSS 6.3 · v4.0—No exploit Fix available
Published
Jul 2, 2026
Updated
Jul 24, 2026
EPSS
0.2% · 14th percentile

Report tools

JSON

Action score

25

Monitor

Low priority for now.

CVSS
25 / 40 · 6.3 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · EEF
6.3
NVD has not scored this yet; the score shown is the CNA’s.

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

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-54887

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
erlangerlang\/otp
erlangerlang\/ssl

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • erlang erlang/otp20.0 and later · before 27.3.4.14
  • erlang erlang/otp28.0 and later · before 28.5.0.3
  • erlang erlang/otp29.0 and later · before 29.0.3
  • erlang erlang/ssl8.2 and later · before 11.2.12.10
  • erlang erlang/ssl11.3 and later · before 11.6.0.3
  • erlang erlang/ssl11.7 and later · before 11.7.3

Versions reported by the vendor

Affected version ranges reported by the assigning authority (EEF). Independent of NVD's CPE analysis and usually ahead of it.

  • Erlang OTP

    • 8.2 and lateraffected · otpfixed in 11.7.3, 11.6.0.3, 11.2.12.10
    • 20.0 and lateraffected · otpfixed in 29.0.3, 28.5.0.3, 27.3.4.14
    • e594aad2f87aab39e99fccf9e021bc94e0bbf7d4 and later · before 888e3bcd72d5406016b9e0de741026bc2a6f114daffected · git

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12erlangfrom 0—
Debian:13erlangbefore 1:27.3.4.1+dfsg-1+deb13u31:27.3.4.1+dfsg-1+deb13u3
Debian:14erlangbefore 1:29.0.3+dfsg-11:29.0.3+dfsg-1
openSUSE:Tumbleweederlangbefore 28.5.0.4-1.128.5.0.4-1.1
openSUSE:Tumbleweederlang27before 27.1.3-3.127.1.3-3.1
SUSE:Linux Enterprise Module for Server Applications 15 SP7erlangbefore 23.3.4.19-150300.3.39.123.3.4.19-150300.3.39.1
SUSE:Linux Enterprise Module for Server Applications 15 SP7erlang26before 26.2.1-150300.7.28.126.2.1-150300.7.28.1

Same product

erlang: all records

Other highest-scoring records for the same primary product.

  • CVE-2025-32433Erlang/OTP SSH Vulnerable to Pre-Authentication RCEKEV
    100Now
  • CVE-2022-37026In Erlang/OTP before 23.3.4.15, 24.x before 24.3.4.2, and 25.x before 25.0.2, there is a Client Authentication Bypass in certain client-cert
    39Monitor
  • CVE-2016-10253An issue was discovered in Erlang/OTP 18.x.
    39Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2026-53422Jul 2, 2026 · SFTP REALPATH path-existence oracle allowing filesystem enumeration outside configured root
    9Monitor
  • ← EarlierCVE-2026-54886Jul 2, 2026 · SSH SFTP server denial of service via extended channel data infinite loop
    21Monitor
  • Later →CVE-2026-54891Jul 2, 2026 · Plaintext APPLICATION_DATA injected during TLS handshake delivered to client application post-handshake in ssl
    25Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Erlang OTP11.2.12.10Vendor (CNA)
Erlang OTP11.6.0.3Vendor (CNA)
Erlang OTP11.7.3Vendor (CNA)
Erlang OTP27.3.4.14Vendor (CNA)
Erlang OTP28.5.0.3Vendor (CNA)
Erlang OTP29.0.3Vendor (CNA)
Erlang OTP888e3bcd72d5406016b9e0de741026bc2a6f114dVendor (CNA)
azl3 erlang 26.2.5.21-4 on Azure Linux 3.026.2.5.21-5 · CBL-Mariner ReleasesMicrosoft (MSRC)
debian:erlang1:27.3.4.1+dfsg-1+deb13u3 · Debian:13Package registry (OSV)
opensuse:erlang28.5.0.4-1.1 · openSUSE:TumbleweedPackage registry (OSV)
opensuse:erlang2727.1.3-3.1 · openSUSE:TumbleweedPackage registry (OSV)
suse:erlang23.3.4.19-150300.3.39.1 · SUSE:Linux Enterprise Module for Server Applications 15 SP7Package registry (OSV)
suse:erlang2626.2.1-150300.7.28.1 · SUSE:Linux Enterprise Module for Server Applications 15 SP7Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
Integrity
Availability
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
X

Weakness class (CWE)

CWE-1394 · Use of Default Cryptographic Key

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/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

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (4 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records