Malicious PDF — malware analysis report

Static analysis result for SHA-256 3bf9b2c56111fbe6…

MALICIOUS

PDF

75.9 KB Created: 2021-09-23 03:37:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9ecdba910324440db18520d809946662 SHA-1: 726999d76f57c6163f4437df3d2167af9040c371 SHA-256: 3bf9b2c56111fbe6d7415138667d91862ba8f2e75bd545b8536c5ae1e67ba20f
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF acts as a link farm, potentially leading to a download, and includes a callback lure, suggesting a phishing or scam attempt. The presence of multiple external URIs and a compromised CMS upload link further supports this. No scripts were extracted, but the overall structure points to a social engineering attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://gastriklandsbf.se/UserFiles/files/nidesaguw.pdf
    • https://dailyhondaotomientay.com/upload/files/fovinuxovodixusaxul.pdf
    • http://astprom.ru/sites/default/files/file/34378956971.pdf
    • http://buren-kompanie.de/userfiles/files/62952696483.pdf
    • https://computerzone.pk/file/vowenuzesosini.pdf
    • https://esterkins.de/ckfinder/userfiles/files/nebujaribek.pdf
    • https://www.solucionaesp.com/ckfinder/userfiles/files/kapatogafepu.pdf
    • http://gaongonmaiphuong.vn/webroot/img/files/60790427494.pdf
    • http://aan.kz/ckfinder/userfiles/files/fagefefedukamivijup.pdf
    • http://xn--djr00fsyfv0o5qgy9u.com/filespath/files/20210918202122.pdf
    • http://xn--80aer5aza.xn--c1acndkmcarx.xn--p1ai/ckfinder/userfiles/files/sumomogevaletivunaxubu.pdf
    • https://miltonmattox.com/userfiles/file/15792946917.pdf
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613950d30c82f---35675962925.pdf
    • https://seeandhearbetter.ie/img/shop/contents/zijifefaxoxofebofeketezo.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147ea78d9c1a---34014341895.pdf
    • https://greenways.at/userfiles/file/kapafaponuna.pdf
    • http://sictombbi.fr/ckfinder/userfiles/files/68503812272.pdf
    • https://birsamundapark.in/userfiles/files/pufozakuzoma.pdf
    • http://wirheiraten.de/images/file/81031209672.pdf
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/161345b2c9f8c8---5074914131.pdf
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613059d006ce1---sezataluzorevaf.pdf
    • http://demenagements-remond.fr/userfiles/file/20210920140840.pdf
    • https://ags-car.com/upload/files/fafunivotikuw.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=play+store+pc+apps+free+download
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bd63.bin
0327b9665f737861ead05c81a338de08458c28b5aa0111335e7e334219a83e62
pdf-font-stream PDF embedded font (sfnt) at offset 0xBD63 20120 bytes
font_01_sfnt_off0000f128.bin
70d4849572a639ec68c5cfb298dafd18bc4c09e08eca0d67071d3cad39661614
pdf-font-stream PDF embedded font (sfnt) at offset 0xF128 10720 bytes
font_02_sfnt_off00010a15.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A15 16792 bytes