VulnerabilityPublished 11 Nov 2026

CVE-2026-110672: perl-Cpanel-JSON-XS security update

Affects perl-Cpanel-JSON-XSSource GCVE Database

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Mentioned vulnerabilities

Authoritative record:CVE-2026-110672· High 7.5

Not known to be exploited · CVSS 7.5 High : upgrade to 4.80-1.oe2403sp4 soon.

Data as of 11 Nov 2026, 13:20 UTC

CVSS 3.1 base score

7.5High

How severe the flaw is on the 0–10 CVSS scale.

Thin evidence

One scorer or none

CVSS scores by source
CISA-ADP	CVSS 3.1	7.5

Patch: Available – fixed in 4.80-1.oe2403sp4

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 19 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 11 Nov 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade perl-Cpanel-JSON-XS to 4.80-1.oe2403sp4.

Affected software

Product	Affected	Fixed in
openEuler 24.03-LTS-SP4perl-Cpanel-JSON-XS`pkg:rpm/openEuler/perl-Cpanel-JSON-XS&distro=openEuler-24.03-LTS-SP4`Other threats	Affected <4.80-1.oe2403sp4	Fixed in 4.80-1.oe2403sp4

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

Description

This module converts Perl data structures to JSON and vice versa. Its primary goal is to be correct and its secondary goal is to be fast. To reach the latter goal it was written in C. %package help Summary : CPanel fork of JSON::XS, fast and correct serializing Provides: perl-Cpanel-JSON-XS-doc %description help This module converts Perl data structures to JSON and vice versa. Its primary goal is to be correct and its secondary goal is to be fast. To reach the latter goal it was written in C. %prep %setup -q -n Cpanel-JSON-XS- %build export PERL_MM_OPT=&quot;&quot; Makefile.PL INSTALLDIRS=vendor OPTIMIZE=&quot;$RPM_OPT_FLAGS&quot; make Security Fix(es): Cpanel::JSON::XS versions before 4.80 for Perl leak the decoded key of an object rejected for a duplicate key or a missing colon in decode_hv. A quoted key of 24 or more bytes, or one containing a non-ASCII byte or an escape sequence, is decoded into a new scalar. Nothing frees that scalar when the object is rejected for a missing ':' after the key or, from 4.09, for a duplicate key. Duplicate keys are an error unless allow_dupkeys, dupkeys_as_arrayref or relaxed is set. A process that keeps running after a failed decode retains one key per rejected document, with its size chosen by the sender. Repeated requests exhaust process memory.(CVE-2026-110672) Cpanel::JSON::XS versions from 4.33 before 4.80 for Perl miss duplicate non-ASCII bare keys, allowing type confusion under dupkeys_as_arrayref in decode_hv. With allow_barekey, which relaxed enables, a bare key containing a non-ASCII byte is stored as UTF-8 but looked up as raw bytes, so a repeated key escapes the duplicate-key check and replaces the earlier value. From 4.41, under dupkeys_as_arrayref, a bare repeat replaces the array that collects a key's values with a plain value, and the next quoted repeat pushes onto that value as if it were an array. A JSON integer there is dereferenced as a pointer. Untrusted JSON decoded with relaxed and dupkeys_as_arrayref can crash the process or dereference an address chosen by a JSON number.(CVE-2026-110674) Cpanel::JSON::XS versions from 4.33 before 4.80 for Perl accept malformed UTF-8 in bare hash keys under allow_barekey in decode_hv. With utf8 and allow_barekey, which relaxed enables, a quoted key is validated as UTF-8 but a bare key's bytes are stored as a UTF-8 flagged string without any check. Malformed UTF-8, control bytes and backslashes reach the decoded hash, while malformed UTF-8 and control bytes in a quoted key or a value are rejected. Later operations on the key, including lc, uc or encoding the hash again, die with a malformed UTF-8 error.(CVE-2026-110675) Cpanel::JSON::XS versions before 4.80 for Perl allow memory exhaustion by encoding exponent notation as full decimal digits under allow_bignum. With allow_bignum, a JSON number with a fraction or exponent decodes to a Math::BigFloat, which stores the exponent separately and so decodes cheaply. Encoding it untyped or as JSON_TYPE_FLOAT writes the plain decimal form with one digit per unit of exponent. Nothing bounds the exponent, so the 12-byte text [1e30000000] encodes to 30 MB. Untrusted JSON decoded with allow_bignum and encoded again can exhaust memory and CPU.(CVE-2026-110676) Cpanel::JSON::XS versions from 4.28 before 4.80 for Perl leak the array collecting duplicate key values under dupkeys_as_arrayref in decode_hv. With dupkeys_as_arrayref, the values of a duplicate object key are collected into a new array. An extra reference is never released, so the array and every value in it outlive the decoded structure. The array also leaks when decoding fails after a duplicate key. Repeatedly decoding untrusted JSON with a duplicate key holding a large value exhausts process memory.(CVE-2026-110677) Cpanel::JSON::XS versions before 4.80 for Perl allow memory exhaustion by buffering incremental input past max_size in incr_parse. The parser appends each chunk to its buffer. In scalar or list context, it compares max_size with how far it has progressed, not with the buffer length. A chunk that starts with a NUL byte stops the parser before it progresses, and a call in void context skips the check, so the buffer grows without limit. A peer streaming data to an incr_parse consumer can exhaust process memory regardless of max_size.(CVE-2026-110678) Cpanel::JSON::XS versions from 4.20 before 4.80 for Perl write out of bounds when a tied or shared hash grows during canonical encoding in encode_hv. With canonical, the keys of a tied or threads::shared hash are counted before a second pass collects them for sorting. The encoder uses a fixed 64-entry stack array or, for larger counts, a heap array sized from the first pass. If the second pass exceeds that capacity, entries are written out of bounds before the counts are compared. This corrupts stack or heap memory and can crash the process.(CVE-2026-110680) Cpanel::JSON::XS versions before 4.80 for

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