VulnerabilityPublished 12 Mar 2026

CVE-2026-3977: projectsend · Missing Authorization

Affects projectsendSource CVE Database V5

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Not known to be exploited · CVSS 5.3 Medium.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 4.0 base score

5.3Medium

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 21% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:X

Attack Vector: Network
Attack Complexity: Low
Attack Requirements: None
Privileges Required: Low
User Interaction: None
Vulnerable system confidentiality: Low
Vulnerable system integrity: Low
Vulnerable system availability: Low
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

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

Attack Vector: Network: The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, 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: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: Low: The attacker requires privileges that provide basic capabilities that are typically limited to settings and resources owned by a single low-privileged user. Alternatively, an attacker with Low privileges has the ability to access only non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without interaction from any human user, other than the attacker.
Vulnerable system confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the Vulnerable System.
Vulnerable system integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact to the Vulnerable System.
Vulnerable system availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the Vulnerable System are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the Vulnerable System.
Subsequent system confidentiality: None: There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 12 Mar 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 30 Oct 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

Affected software

Product	Affected	Fixed in
projectsend	Affected =r1945	Fixed in–

CPE configurations (1)

cpe:2.3:a:projectsend:projectsend:*:*:*:*:*:*:*:*

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

AI-suggested

Organizations should immediately apply the patch identified by commit 35dfd6f08f7d517709c77ee73e57367141107e6b to all affected ProjectSend instances. Beyond patching, conduct a thorough review of all AJAX endpoints to ensure robust authorization checks are implemented consistently. Implement strict access control policies and monitor logs for unusual access patterns or unauthorized requests targeting AJAX endpoints. Employ network segmentation and firewall rules to limit exposure of ProjectSend servers to trusted networks only. Regularly audit user privileges to minimize the number of accounts with elevated access. Consider deploying web application firewalls (WAFs) with custom rules to detect and block suspicious AJAX requests. Educate administrators on secure configuration practices and maintain up-to-date backups to enable recovery in case of compromise. Finally, stay informed on any emerging exploit reports or additional patches related to ProjectSend.

Description

A security vulnerability has been detected in projectsend up to r1945. The affected element is an unknown function of the component AJAX Endpoints. The manipulation leads to missing authorization. The attack can be initiated remotely. The identifier of the patch is 35dfd6f08f7d517709c77ee73e57367141107e6b. To fix this issue, it is recommended to deploy a patch.

Impact

The missing authorization vulnerability in ProjectSend could allow attackers to remotely access or manipulate sensitive files and data without proper permissions. This compromises confidentiality by exposing potentially sensitive information, integrity by allowing unauthorized modification of data, and availability if attackers disrupt file sharing services. Organizations relying on ProjectSend for secure file transfers, including businesses, educational institutions, and government agencies, face risks of data breaches, regulatory non-compliance, and operational disruption. The vulnerability's exploitation could lead to unauthorized disclosure of confidential files, data tampering, or denial of service conditions. Since the flaw requires low privileges and no user interaction, attackers with limited access could escalate their capabilities, increasing the threat scope. The absence of known exploits currently reduces immediate risk but does not eliminate the potential for future attacks. Failure to patch promptly could result in targeted attacks, especially in sectors where secure file sharing is critical.

References

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