Malicious PDF — malware analysis report

Static analysis result for SHA-256 a14a3efe1a036c27…

MALICIOUS

PDF

12.0 KB
MD5: c710b81e55dd2d61cf81880f8aa7f525 SHA-1: 81ff060f3f7a0b4d2bd5912bdaffb769efd4df82 SHA-256: a14a3efe1a036c270487480dada3c3b9abe5d83e2ba892792ea097e4ebddf8ef
186 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link

The PDF contains embedded JavaScript that leverages the CVE-2007-5659 vulnerability (Collab.collectEmailInfo). This JavaScript is heavily obfuscated but appears to function as a stager, decoding and executing further malicious code. The primary mechanism involves exploiting a PDF vulnerability to run arbitrary JavaScript, which is then used to download and execute a secondary payload. The ClamAV detection also confirms the malicious nature of the file.

Heuristics 7

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • ClamAV: Pdf.Exploit.Agent-36063 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36063
  • Annotation subject callee-key hex JavaScript stager high PDF_ANNOT_SUBJECT_CALLEE_HEX_STAGER
    PDF JavaScript uses syncAnnotScan()/getAnnots() to read an indirect annotation /Subject stream, percent-decodes it through marker replacement, then uses a callee.toString()-derived key to decode and eval the final exploit stage.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • syncAnnotScan annotation-staging primitive low PDF_FOXIT_SYNCANNOTSCAN
    PDF JavaScript calls syncAnnotScan() — a no-op annotation-enumeration primitive used by exploit-kit JavaScript to stage payload reads from annotation /Subject fields before eval(). Not a vulnerable sink itself; rarely seen in legitimate PDFs. (matched in decompressed stream)
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
eb39e2de4dbbc100de6d3e30aa43ff78fa075618862ba1ebba5151ea3a3b848d
pdf-javascript-stream PDF /JS object 7 at offset 0x19D 273 bytes
annotation_subject_callee_hex_stage_000.js
bf2c24be881405453e86f23893a559b3ef835ac9b9482d72d51fdec1943e2aac
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5194 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
3c38552edd2c7e04c4f178b4c6d50c1ce9e074c95498bf8acacb0e659779d566
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12338 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
deobfuscated.js
f8267d41676fde79ec93e7a85ce6e2ab1b5c288bb3ebf8eedb5c9cc0a451c9cf
deobfuscated-js PDF JavaScript deobfuscation pass 78189 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).