CVE Intelligence
Medium Input validation exploit reference

CVE-2026-107225 — Excelize: GetStyle panics on a negative fillId, borderId or fontId in styles.xml

Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.8.0 to 2.11.0, GetStyle's fill, border, and font extraction predicates check only upper bounds for attacker-controlled style-table indices. File.GetStyle relies on extractStyleCondFuncs predicates that allow negative FillID, BorderID, and FontID values to reach slice indexing. When a crafted styles.xml supplies a negative fillId, borderId, or fontId and the application reads the style, a negative identifier passes the upper-bound-only predicate and becomes a negative slice index, allowing an attacker to panic while reading cell styling. No fixed version is available as of this review.

Published Oct 7, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, GitHub Security Advisories, CVE Program (cve.org) e CISA ADP · CNA: GitHub_M

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 0.3% (30-day exploitation probability)+2
  • Technical severity (medium)+3
  • CISA SSVC: exploitation "poc"+5

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
0.25%
ahead of 16% of scored CVEs · Oct 15, 2026
Affects
Excelize
Excelize and 1 more
CVSS base
6.5
Medium · 3 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
Proof of concept
none · proof-of-concept · active
Automatable
No
can an attacker script the kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component

Remediation

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

  • Documented patch — github.com (NIST National Vulnerability Database)
  • Documented patch — github.com (NIST National Vulnerability Database)
  • Go Github.com/xuri/excelize/v2: fixed in version 2.11.1-0.20260731010303-ae2113b410e5 — github.com (GitHub Security Advisories)

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 (Excelize Excelize, Qax-os Excelize, Go Github.com/xuri/excelize/v2).
  2. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. Apply the fixed version or the patch documented under Remediation.
  4. Exploitation requires user interaction: tighten email/web filtering and warn affected users.
  5. Search available logs for exploit probes matching the vulnerability class (input validation), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Excelize Excelize ≥ 2.8.0 and ≤ 2.11.0 Vulnerable NIST National Vulnerability Database
Qax-os Excelize version >= 2.8.0, <= 2.11.0 Vulnerable CVE Program (cve.org) e CISA ADP
Go Github.com/xuri/excelize/v2 ≥ 2.8.0 and < 2.11.1-0.20260731010303-ae2113b410e5 Vulnerable GitHub Security Advisories

Attack characteristics

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

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Every base score collected

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

ScoreVersionSeverityExpl.ImpactScored by
6.5 CVSS 3.1 Medium 2.8 3.6 security-advisories@github.com via NIST National Vulnerability Database
6.5 CVSS 3.1 Medium — — GitHub, Inc. via GitHub Security Advisories
6.5 CVSS 3.1 Medium — — GitHub_M via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H (score shown at the top: security-advisories@github.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-20 · Improper Input Validation

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 15, 2026 · 3 reading(s) · max 0.25%

Detection

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

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · qax-os/excelize
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Fix documented
    Oct 13, 2026 · GitHub Security Advisories
  • Affected products added · go/github.com/xuri/excelize/v2
    Oct 13, 2026 · GitHub Security Advisories
  • Record published
    Oct 13, 2026
  • Fix documented
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVSS changed · 6.5
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Analyzed
    Oct 13, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVE published
    Oct 7, 2026 · GitHub_M

Source activity

Repeated readings are counted rather than listed.

  • 1× References added · Oct 13, 2026 – Oct 13, 2026
  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

4 on the record

Elsewhere on this site

Excelize
every CVE for this vendor
CWE-20
other pages naming this weakness

Related CVEs (same products)

  • Medium CVE-2026-107224 Excelize: A Zip64 uncompressed-size of 2^63 panics OpenFile/OpenReader 8d
  • Medium CVE-2026-107218 Excelize: RIGHT() on supplementary-plane text slices with a negative index and panics 8d
  • Medium CVE-2026-107222 Excelize: GetConditionalFormats indexes conditional-formatting rule sub-elements with no length or nil check 8d
  • High CVE-2026-107219 Excelize: Unbounded spinCount in agile decryption burns CPU during OpenFile 8d
  • Medium CVE-2026-107220 Excelize: Panic in cellInRange on a worksheet with an empty mergeCell ref 8d
  • Medium CVE-2026-107221 Excelize: a row whose earlier cell has a higher column reference than its last cell panics index out of range on almost every worksheet read API 8d

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 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-2026-107225 is "Excelize: GetStyle panics on a negative fillId, borderId or fontId in styles.xml", rated Medium. It affects Excelize (Excelize); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 6.5 describes technical severity. EPSS 0.25% 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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