Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc55be0cfd7bce42…

MALICIOUS

PDF

71.5 KB Created: 2021-06-28 11:53:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 40655f482cdd3090dab9c4df4f6d9bf5 SHA-1: 3f75a4448411b556698b95d2c52cbb200873e4fa SHA-256: dc55be0cfd7bce42d7a0789f3173f0f8876900bc3b0f8ec00a045b8f9c05390e
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, indicating an attempt to distribute malicious content or conduct phishing. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of numerous external URIs and a link farm heuristic confirms the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://jarosi.hu/files/file/baxivurovot.pdf
    • http://slp70.com/clients/873855/File/wusagiv.pdf
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/d33j3nb8rhrvm4u9efem3uqvm1/12277659302.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16079d2d065ea5---87385178981.pdf
    • https://dixietemporarystorage.com/wp-content/plugins/super-forms/uploads/php/files/2d50493f2dbb0734dedf06151e2f3935/25188712922.pdf
    • https://roeveragri.ac.in/wp-content/plugins/super-forms/uploads/php/files/f0d4b3bf82b316c0a226ed2a13ddb04b/vobevolazodovibakusez.pdf
    • http://staging.impactredevelopment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160756d76beb18---pagoxi.pdf
    • http://lctrading-gmbh.com/ckfinder/userfiles/files/potojagijirexijasaso.pdf
    • http://vssteel1999.com/ckeditor/userfiles/files/7169112911.pdf
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/160a4b26d63798---56438261427.pdf
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16082e68b13f1d---45396908009.pdf
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/b269be078cb20601434a86a8d27c0b14/reripizajotuwog.pdf
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608dfc2fdd404---torekoruj.pdf
    • https://big-cash.de/wp-content/plugins/super-forms/uploads/php/files/4qgfr0heq37e6vi2squs0b3uil/doribatikisif.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/8771317ba02df693d0f340ff5da2939f/70220524736.pdf
    • http://firanywiktoria.pl/uploads/editor/file/vunagoferivorenevum.pdf
    • http://easyliveconstruction.com/ci/userfiles/files/56611767929.pdf
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/c385488c7b28b1174e791baadad8624e/61802731641.pdf
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/932b09019f38fb78427e5439dcee9f21/rovebix.pdf
    • https://nolimitscenter.be/peausitive/images/FCKeditor/file/12355239005.pdf
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a753563f04b---4626078135.pdf
    • http://work4shop.cz/userfiles/file/peponigepitemipigip.pdf
    • https://ambientltg.com/wp-content/plugins/super-forms/uploads/php/files/6046b79574f430f192fc02692fb9afdb/61439121926.pdf
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/1c524bea539321789a754908fa5647b9/pedililedugesujuwuserud.pdf
    • http://simonide.org/userfiles/file/dafifikosozubavu.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=pdf+for+all
    • 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_off0000bc36.bin
4fc3cecf629de247eecef1f7bd1fa69c3df348a121539dfe412b55243a36a938
pdf-font-stream PDF embedded font (sfnt) at offset 0xBC36 15644 bytes
font_01_sfnt_off0000e3c1.bin
5e506decf2e82fa493132a3d46597f3c1f9e4f257797c84cb6303d9f89a9cc6b
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3C1 9752 bytes
font_02_sfnt_off0000f923.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF923 16792 bytes