CVE Intelligence
Medium Denial of service

CVE-2026-96596 — erl_tar:extract/2 loops forever on a GNU sparse member with a trailing hole

Loop with Unreachable Exit Condition ('Infinite Loop') vulnerability in Erlang OTP stdlib (erl_tar module), hexpm hex_core (hex_erl_tar module), hexpm hex (mix_hex_erl_tar module) and erlang rebar3 (r3_hex_erl_tar module) allows an attacker who supplies a tar archive to cause a denial of service via a crafted GNU sparse member. When erl_tar:extract/1,2 writes a member to disk, erl_tar:stream_to_file_loop/3 reads it in chunks of 65536 bytes by default. For a GNU sparse member whose sparse map ends before its real size, erl_tar:do_sparse_read/3 matches its trailing-hole clause before its zero-length clause. After the chunk is used up, the trailing-hole clause reads zero bytes, does not advance the position, and recurses forever. A 2048-byte archive keeps the extracting process and one scheduler busy until the process is killed. The {max_size, N} option prevents this only when N is below the real size of the member. Extraction with the memory option is not affected. hex_core ships its own copy of erl_tar as hex_erl_tar, and Hex and rebar3 ship hex_core with prefixed module names (mix_hex_erl_tar and r3_hex_erl_tar). These copies contain the same code and do not call stdlib's erl_tar, so they are affected on any OTP version. OTP 28 is not affected, but an application running on OTP 28 is affected if it extracts archives through an affected version of hex_core, Hex or rebar3. This issue affects OTP from OTP 29.0 before OTP 29.1.2, corresponding to stdlib from 8.0 before 8.1.1, and rebar3 from 3.27.1 onward, and hex from 2.4.2 before 2.5.3; hex_core: from 0.14.0 before 0.20.1.

Published Oct 14, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: EEF

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.2% (30-day exploitation probability)+1
  • Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.18%
ahead of 7% of scored CVEs · Oct 15, 2026
Affects
Erlang
Erlang/otp and 3 more
CVSS base
5.9
Medium · 2 source(s)

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Erlang Erlang/otp, Erlang Rebar3, Hexpm Hex…).
  2. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  3. Search available logs for exploit probes matching the vulnerability class (denial of service), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Erlang Erlang/otp ≥ 29.0 and < 29.1.2≥ 8.0 and < 8.1.1≥ fbf2c7194f6fce4b7b66dc0bcaa4f6b4b85e088f and < 3086307f311b78b38644a7787a3aca6a3f95a9d5 Vulnerable CVE Program (cve.org) e CISA ADP
Erlang Rebar3 ≥ 3.27.1≥ 23dbdb5d1f87f56902aef296c88a20049cd0c6e4 Vulnerable CVE Program (cve.org) e CISA ADP
Hexpm Hex ≥ 5543a1919c709d8eb2b317f62aad76ca1eed375c≥ 2.4.2 and < 2.5.3 Vulnerable CVE Program (cve.org) e CISA ADP
Hexpm Hex Core ≥ 0.14.0 and < 0.20.1≥ 13bb9fbba418a406af614790b8d5cd458259ee70 and < a2ece683e6e88a3ec95ad20b09aca426e08b372e Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Local
Attack complexity
Low
Attack requirements
Present
Privileges required
None
User interaction
None
Scope
X
Confidentiality (vulnerable system)
None
Integrity (vulnerable system)
None
Availability (vulnerable system)
High
Confidentiality (subsequent)
None
Integrity (subsequent)
None
Availability (subsequent)
None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
5.9 CVSS 4.0 Medium — — 6b3ad84c-e1a6-4bf7-a703-f496b71e49db via NIST National Vulnerability Database
5.9 CVSS 4.0 Medium — — EEF via CVE Program (cve.org) e CISA ADP
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/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 (score shown at the top: 6b3ad84c-e1a6-4bf7-a703-f496b71e49db)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-835 · Infinite Loop

Other CVEs with this weakness →

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
  • Track CPU/memory spikes and availability drops correlated with request patterns.
endpoint telemetry (EDR)resource metrics

Timeline

What happened to this CVE, newest first.

  • 2026
  • Source status changed · Received → Deferred
    Oct 15, 2026 · NIST National Vulnerability Database
  • Affected products removed · 6
    Oct 14, 2026 · CVE Program (cve.org) e CISA ADP
  • Affected products added · erlang/otp, hexpm/hex core, hexpm/hex
    Oct 14, 2026 · CVE Program (cve.org) e CISA ADP
  • Affected products added · erlang/otp, erlang/rebar3, hexpm/hex, hexpm/hex core
    Oct 14, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 14, 2026
  • CVSS changed · 5.9
    Oct 14, 2026 · NIST National Vulnerability Database
  • Source status changed · → Received
    Oct 14, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 14, 2026 · Alertas do Telegram
  • CVE published
    Oct 14, 2026 · EEF

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 14, 2026 – Oct 14, 2026
  • 2× Official description updated · Oct 14, 2026 – Oct 14, 2026

References

12 on the record

Elsewhere on this site

Erlang
every CVE for this vendor
Denial of service
same class
CWE-835
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-94200 TLS 1.3 client ticket store crashed by NewSessionTicket with empty early_data extension in ssl 1d
  • CVE-2026-105236 TLS 1.2 session resumption in ssl crosses SNI virtual-host client-certificate trust boundaries 1d
  • CVE-2026-105274 hex_core decompresses registry and Erlang term API responses without size limits 3d
  • CVE-2026-96618 Hex exhausts memory and disk on oversized or compressed responses from an untrusted mirror 3d
  • CVE-2026-96612 Path traversal in Hex via unvalidated dependency app names 3d
  • CVE-2026-81856 Terminal escape sequence injection in Hex via unneutralized server-supplied output 3d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No fixed version, patch or mitigation documented.
  • No CISA SSVC assessment.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-96596 is "erl_tar:extract/2 loops forever on a GNU sparse member with a trailing hole", rated Medium. It affects Erlang/otp (Erlang); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.9 describes technical severity. EPSS 0.18% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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