CVE-2026-2703 (GCVE-0-2026-2703)
Vulnerability from cvelistv5 – Published: 2026-02-19 04:02 – Updated: 2026-02-24 01:40 X_Open Source
VLAI
EPSS
VEX
Title
xlnt-community xlnt Encrypted XLSX File base64.cpp decode_base64 off-by-one
Summary
A weakness has been identified in xlnt-community xlnt up to 1.6.1. Impacted is the function xlnt::detail::decode_base64 of the file source/detail/cryptography/base64.cpp of the component Encrypted XLSX File Parser. Executing a manipulation can lead to off-by-one. The attack requires local access. The exploit has been made available to the public and could be used for attacks. This patch is called f2d7bf494e5c52706843cf7eb9892821bffb0734. Applying a patch is advised to resolve this issue.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-24 01:40 UTC
Assigner
References
7 references
| URL | Tags |
|---|---|
| https://vuldb.com/?id.346649 | vdb-entrytechnical-description |
| https://vuldb.com/?ctiid.346649 | signaturepermissions-required |
| https://vuldb.com/?submit.754377 | third-party-advisory |
| https://github.com/xlnt-community/xlnt/issues/137 | issue-tracking |
| https://github.com/oneafter/0128/blob/main/xl1/repro | exploit |
| https://github.com/xlnt-community/xlnt/commit/f2d… | patch |
| https://github.com/xlnt-community/xlnt/ | product |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| xlnt-community | xlnt |
Affected:
1.6.0
Affected: 1.6.1 |
guessed |
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
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Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline
Sightings and recorded dates, grouped by day · UTC
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.