Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d144a33eb12a7f4…

MALICIOUS

PDF

73.1 KB Created: 2021-09-04 15:37:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 61c059cc78a02991cd32f1ea9aeab6c5 SHA-1: 281662b49a4a7f76dff9fd0e68f5426e409b95a3 SHA-256: 6d144a33eb12a7f4a9f1ba1cc19090bcf579e0cc98e5ff4bebf682c93eb09448
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate it functions as a link farm, directing users to numerous external URLs, some hosted on compromised WordPress sites. The PDF's structure and embedded content suggest it is designed to exploit users by directing them to potentially harmful websites, likely for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://oniceh.ru/uplcv?utm_term=examen+quimica+organica+bachillerato+pdf
    • http://www.pavimentosyreformasferlu.es/ckfinder/userfiles/files/35805491075.pdf
    • https://le27.fr/docs/file/ridodigojogiv.pdf
    • http://veterinariomauracotti.it/userfiles/files/gexuxekidasakawavukemej.pdf
    • https://firsatoyun.com/calisma2/files/uploads/faxixadimomu.pdf
    • http://greatnice.club/updatefiles/file/70184702693.pdf
    • http://vaynhe.com/upload/files/63284642352.pdf
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/16082cac0a7f6f---11376624258.pdf
    • http://bhk-aindling.de/userfiles/files/bajirajesamolaxerofefu.pdf
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d38d843c747---125403986.pdf
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/160767a1aad2b2---9626456894.pdf
    • https://cengilli.com/icerik_images/file/lomeneno.pdf
    • http://arch-teh.com/pic/userfile/nowiwovoxidoko.pdf
    • http://arlingtonhigh1960.com/clients/881088/File/18809495858.pdf
    • https://cobaltinc.org/userfiles/file/58758919826.pdf
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b62744774e5---bexevizexazagalevusokasiz.pdf
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/bs22l7499mqo80uuh5c1db850p/63631627473.pdf
    • http://hillsdalehorseboarding.com/ckfinder/userfiles/files/ralonuwaso.pdf
    • https://www.bakirkoytemsilcisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608020f42dad4---62985253672.pdf
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/1608c2e4c56dc0---jagekijonafilupet.pdf
    • http://glovimex.com/uploads/ckfinder/files/bafovorusasunapisa.pdf
    • http://shuimotongyuan.com/userfiles/file/25257609876.pdf
    • http://thebankcardservice.com/uploads/files/87374303795.pdf
    • https://rubenoferro.com/userfiles/file/63256840564.pdf
    • 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_off0000b9aa.bin
53523b3b175ca0607d46f5bba0cbba157343656da36770599c44ba9b73f40382
pdf-font-stream PDF embedded font (sfnt) at offset 0xB9AA 17676 bytes
font_01_sfnt_off0000e551.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE551 16792 bytes
font_02_sfnt_off0000fd68.bin
4e5b527aa50020ec2f1aa717e5bb3e72eec0b69786f61993f30c070fce3f698a
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD68 11372 bytes