Malicious PDF — malware analysis report

Static analysis result for SHA-256 c54e3a8a914972e2…

MALICIOUS

PDF

87.6 KB Created: 2021-06-28 17:49:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bd890702f9c3090a9f641a5138585a2a SHA-1: 213b2ca26c4706d8cce7616a847406ad8b274575 SHA-256: c54e3a8a914972e25489ae79bf1487b5b60070f1517e1f9958b58868dd88ef79
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to external websites, many hosted on compromised CMS upload directories, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, lacking clear user-facing text but containing embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • 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.
  • 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 http://adamlegal.com/userfiles/file/37397480348.pdf
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16078161973707---21038858389.pdf
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/db052e810d96396e0a8adb15aba646d7/jinudisabirexixerosisetoz.pdf
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/60d7a06400674faddce7ea6198fe9046/dutuko.pdf
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/d3e3e0c065a5af24f36c8c35d687dbb1/49410474718.pdf
    • http://rajskiewakacje.pl/userfiles/file/17860964968.pdf
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/222m3jbksj1froo6t1v9hakqi4/gitofapolalolad.pdf
    • http://abacusnancy.com/userfiles/file/kufanapuvaxabemof.pdf
    • http://ankurgroups.com/userfiles/file/68200928813.pdf
    • https://myclubowners.com/userfiles/files/zururimapiritemilosev.pdf
    • https://carrieres-pierre.com/userfiles/file/gekuvofabesixolafotedos.pdf
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/b8aa69c78643ad5e2f9b47426519ddd7/kovegoj.pdf
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160719499a2a28---27128415978.pdf
    • https://biorenta.lt/ckfinder/userfiles/files/27337475632.pdf
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae52161578f---fatowolaxo.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/0215ec557132a9929be3be74ca0c8c14/26648015331.pdf
    • http://akkoryazilim.com/userfiles/file/setimumiwaterotovukura.pdf
    • https://big-cash.de/wp-content/plugins/super-forms/uploads/php/files/44nfqh6mdijkmb56a8cr69vu8o/numoxawepuvadawomagusite.pdf
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097b0124225f---vulujutavubaxixokunup.pdf
    • http://dungcubepgiangtrinh.com/webroot/img/files/75480961373.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=excursions+near+me
    • 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_off0000f550.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF550 16792 bytes
font_01_sfnt_off00010d62.bin
32f0ea01bcbc32d79c55d18080abdb196b5b0038f3ae23586adeca6584e59a6d
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D62 17164 bytes
font_02_sfnt_off00013a1b.bin
c3152db69aa647b13dae7315f6fd29655040372bd192d07b6f8190e6b005270c
pdf-font-stream PDF embedded font (sfnt) at offset 0x13A1B 10432 bytes