Malicious PDF — malware analysis report

Static analysis result for SHA-256 937c4c9a6ec8a4d8…

MALICIOUS

PDF

87.9 KB Created: 2021-07-03 14:48:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 161884551e05dbf1ec3f837a066cc794 SHA-1: da6eec0ca371c00f1219cb678e238bc6beeccca3 SHA-256: 937c4c9a6ec8a4d8619957e82f5abe3f6162914afe8c1c9a4bbb81d3c738284f
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to what appear to be compromised WordPress sites, specifically within form upload directories. Heuristics indicate this is a link farm on disposable hosting, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b394bebabf---lenuvatavidoributovifol.pdf
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/e7a28d9161f7d7941d26e188906ffae1/kudujileviwe.pdf
    • https://prosegik.com/wp-content/plugins/super-forms/uploads/php/files/7e009874d4b8f3320fbb6fec7bc7d1e8/xavowofanuwovezo.pdf
    • http://akinmedikal.com/uploads/file/sisekilaxogasezagutop.pdf
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16072ffb1871e1---besojugutawipelekogixa.pdf
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b75aaa8c142---lawimogosesizakulo.pdf
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/940eac0bc18b77b1100b1ab98aaa43b6/61092234951.pdf
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc22c355fd1---jotoxumolabixoraki.pdf
    • https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/2b293e314812aa448bd2cd3b9c4d302a/kebipataxovutejafe.pdf
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b859e915a67---dibenifexumumozokaruk.pdf
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160975b4711de8---jixovuv.pdf
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a3a6debbb4---fulujikuromokonax.pdf
    • https://auto-rujo.com/images-editor/file/zejejurejedez.pdf
    • http://mousike.it/img_ins/files/84657506321.pdf
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/8d72f6919d075c46f325eea95a91555a/85955419570.pdf
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dc3c5ae367---xedujodotijutarimaf.pdf
    • https://www.azembay.com/wp-content/plugins/super-forms/uploads/php/files/pvpitvudltumkra72lc6jbki5j/fajabefaj.pdf
    • http://bjhtdszdh.com/v15/Upload/file/20215161529348004.pdf
    • https://hagepoorter.be/files/files/76377581716.pdf
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/9188b4d959c0db5681ec2511d3d7730d/dupowerokupuziput.pdf
    • http://app8itebarandgrill.com/admin/images/file/82656467056.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=meaning+of+canker
    • 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_off0000f2fe.bin
6da1478b18d493b948f9a9df78db1dbca2b8225e3bd4c8680f74b1356d7f768a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2FE 18600 bytes
font_01_sfnt_off0001238b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1238B 16792 bytes
font_02_sfnt_off00013ba2.bin
58df5abff9eaef90367deb94eb1112513d1efd141bdd5246ba5215b2c99d3ec8
pdf-font-stream PDF embedded font (sfnt) at offset 0x13BA2 10284 bytes