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NVD / CVE Program· CNA EEF

CVE-2026-55737: Heap pointer corruption via signed/unsigned mismatch in LARGE_TUPLE_EXT decoding in erts external term format decoder

Noroxi assessment

Priority: Monitor (action score 20/100)

  • 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: 0.28% (FIRST EPSS).
  • Someone with local access to the system 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 15.2.7.11, 16.4.0.4, 17.0.4; azl3 erlang 26.2.5.21-4 on Azure Linux 3.0 26.2.5.21-3.

Low priority for now. Upgrade to Erlang OTP 15.2.7.11, 16.4.0.4, 17.0.4; azl3 erlang 26.2.5.21-4 on Azure Linux 3.0 26.2.5.21-3 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

Signed to Unsigned Conversion Error and Out-of-bounds Write vulnerability in Erlang OTP erts allows an attacker who can supply a crafted Erlang external term format (ETF) binary to binary_to_term/1 to corrupt the BEAM heap pointer and crash the virtual machine. When decoding a LARGE_TUPLE_EXT term, the validation pass decoded_size() in erts/emulator/beam/external.c reads the 32-bit arity field as unsigned (get_uint32()), while the decode pass dec_term() reads the same field as a signed 32-bit integer (get_int32()) into an int. An arity wire value of 0x80000000 passes validation as 2147483648 but decodes as -2147483648, so the subsequent hp += n moves the heap allocation pointer backward. Neither pass enforces the runtime tuple-arity limit MAX_ARITYVAL. The result is an out-of-bounds heap write; in practice the VM detects an impossible heap size and aborts, denying service. The required padding is large when uncompressed but the compressed-ETF envelope shrinks it to a small payload on the wire. This issue affects OTP from OTP 25.0 before OTP 29.0.4, OTP 28.5.0.4 and OTP 27.3.4.15, corresponding to erts from 13.0 before 17.0.4, 16.4.0.4 and 15.2.7.11.

MediumCVSS 5.1 · v4.0—No exploit Fix available
Published
Jul 27, 2026
Updated
Oct 24, 2026
EPSS
0.2% · 21th percentile

Report tools

JSON

Action score

20

Monitor

Low priority for now.

CVSS
20 / 40 · 5.1 / 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
5.1
NVD has not scored this yet; the score shown is the CNA’s.

CVSS:4.0/AV:L/AC:L/AT:N/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-2026-55737

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
erlangerts

Affected versions

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

  • erlang erlang/otp25.0 and later · before 27.3.4.15
  • erlang erlang/otp28.0 and later · before 28.5.0.4
  • erlang erlang/otp29.0 and later · before 29.0.4
  • erlang erts13.0 and later · before 15.2.7.11
  • erlang erts16.0 and later · before 16.4.0.4
  • erlang erts17.0 and later · before 17.0.4

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

    • 13.0 and lateraffected · otpfixed in 17.0.4, 16.4.0.4, 15.2.7.11
    • 25.0 and lateraffected · otpfixed in 29.0.4, 28.5.0.4, 27.3.4.15
    • ebcbb97b4ec223464cac3d94375739a248ddef6e and later · before c5210b42a9d3d96f3d25601942ce8122be0f3761affected · 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 1:29.0.4+dfsg-11:29.0.4+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-2026-55953TLS 1.2 and DTLS client accepts unoffered anonymous cipher suite, bypassing server authentication
    36Monitor
  • CVE-2026-49759Stack buffer overflow in SCTP error cause parsing in inet_drv allows remote VM crash
    35Monitor
  • CVE-2026-59251Denial of service via exponential certificate policy tree growth in path validation
    34Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2026-42792Jul 27, 2026 · epmd permanent DoS via EMFILE on accept(2) in erts
    25Monitor
  • ← EarlierCVE-2026-54890Jul 27, 2026 · BEAM VM crash via integer underflow in binary_to_term BIT_BINARY_EXT decoding
    32Monitor
  • Later →CVE-2026-58227Jul 27, 2026 · TLS/DTLS denial of service via unbounded recursion on cross-signed peer certificate chain
    34Monitor

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 OTP15.2.7.11Vendor (CNA)
Erlang OTP16.4.0.4Vendor (CNA)
Erlang OTP17.0.4Vendor (CNA)
Erlang OTP27.3.4.15Vendor (CNA)
Erlang OTP28.5.0.4Vendor (CNA)
Erlang OTP29.0.4Vendor (CNA)
Erlang OTPc5210b42a9d3d96f3d25601942ce8122be0f3761Vendor (CNA)
azl3 erlang 26.2.5.21-4 on Azure Linux 3.026.2.5.21-3 · 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

  • Someone with local access to the system 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
Local
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
X

Weakness class (CWE)

CWE-195 · Signed to Unsigned Conversion Error

CVSS vector

CVSS:4.0/AV:L/AC:L/AT:N/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