How severe is CVE-2023-26435?

CVE-2023-26435 has a CVSS 3.x base score of 5.0, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2023-26435 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-26435?

CVE-2023-26435 primarily affects Open-xchange Open-xchange Appsuite Backend. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-26435?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-26435 published?

CVE-2023-26435 was published on 2023-06-20 and last updated on 2026-06-17.

CVE-2023-26435

CVE-2023-26435 is a medium-severity vulnerability in Open-xchange Open-xchange Appsuite Backend with a CVSS 3.x base score of 5.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-918.

Key facts

Severity: Medium (CVSS 3.x base score 5.0)
EPSS exploit prediction: 1% (52nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-918
Affected product: Open-xchange Open-xchange Appsuite Backend
Published: 2023-06-20
Last modified: 2026-06-17

Description

It was possible to call filesystem and network references using the local LibreOffice instance using manipulated ODT documents. Attackers could discover restricted network topology and services as well as including local files with read permissions of the open-xchange system user. This was limited to specific file-types, like images. We have improved existing content filters and validators to avoid including any local resources. No publicly available exploits are known.

Frequently asked questions

What is CVE-2023-26435?: It was possible to call filesystem and network references using the local LibreOffice instance using manipulated ODT documents. Attackers could discover restricted network topology and services as well as including local files with read permissions of the open-xchange system user. This was limited to specific file-types, like images. We have improved existing content filters and validators to avoid including any local resources. No publicly available exploits are known.
How severe is CVE-2023-26435?: CVE-2023-26435 has a CVSS 3.x base score of 5.0, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2023-26435 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-26435?: CVE-2023-26435 primarily affects Open-xchange Open-xchange Appsuite Backend. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-26435?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-26435 published?: CVE-2023-26435 was published on 2023-06-20 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:open-xchange:open-xchange_appsuite_backend:*:*:*:*:*:*:*:*
cpe:2.3:a:open-xchange:open-xchange_appsuite_backend:7.10.6:*:*:*:*:*:*:*
cpe:2.3:a:open-xchange:open-xchange_appsuite_backend:7.10.6:revision_39:*:*:*:*:*:*

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