How severe is CVE-2021-43823?

CVE-2021-43823 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-43823 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43823?

CVE-2021-43823 affects Sourcegraph. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-43823?

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

When was CVE-2021-43823 published?

CVE-2021-43823 was published on 2021-12-13 and last updated on 2026-06-17.

CVE-2021-43823

CVE-2021-43823 is a medium-severity vulnerability in Sourcegraph with a CVSS 3.x base score of 6.5. 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-203.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.0
EPSS exploit prediction: 1% (53rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-203
Affected product: Sourcegraph
Published: 2021-12-13
Last modified: 2026-06-17

Description

Sourcegraph is a code search and navigation engine. Sourcegraph prior to version 3.33.2 is vulnerable to a side-channel attack where strings in private source code could be guessed by an authenticated but unauthorized actor. This issue affects the Saved Searches and Code Monitoring features. A successful attack would require an authenticated bad actor to create many Saved Searches or Code Monitors to receive confirmation that a specific string exists. This could allow an attacker to guess formatted tokens in source code, such as API keys. This issue was patched in version 3.33.2 and any future versions of Sourcegraph. We strongly encourage upgrading to secure versions. If you are unable to, you may disable Saved Searches and Code Monitors.

Frequently asked questions

What is CVE-2021-43823?: Sourcegraph is a code search and navigation engine. Sourcegraph prior to version 3.33.2 is vulnerable to a side-channel attack where strings in private source code could be guessed by an authenticated but unauthorized actor. This issue affects the Saved Searches and Code Monitoring features. A successful attack would require an authenticated bad actor to create many Saved Searches or Code Monitors to receive confirmation that a specific string exists. This could allow an attacker to guess formatted tokens in source code, such as API keys. This issue was patched in version 3.33.2 and any future versions of Sourcegraph. We strongly encourage upgrading to secure versions. If you are unable to, you may disable Saved Searches and Code Monitors.
How severe is CVE-2021-43823?: CVE-2021-43823 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-43823 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43823?: CVE-2021-43823 affects Sourcegraph. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-43823?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-43823 published?: CVE-2021-43823 was published on 2021-12-13 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:sourcegraph:sourcegraph:*:*:*:*:*:*:*:*

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