Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b89678064dacc37…

MALICIOUS

PDF

90.4 KB Created: 2021-08-03 18:41:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 08a7adacdac9a93db10fe4935617cac1 SHA-1: 0b328dd45676d651a5362d01d3bb6161198aa15a SHA-256: 3b89678064dacc3742597491a78edb8dddf861be76f96eb68d82a5d867a1a428
156 Risk Score

Malware Insights

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

The PDF was flagged by multiple heuristics as a link farm, with several URLs pointing to compromised WordPress upload directories. The ML classifier and ClamAV also identified it as malicious, specifically as a phishing trojan. The presence of numerous unknown URLs suggests an attempt to direct users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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://tz5168.com/uploadfile/image/2021/05/14/file/20210514_193417_100.pdf
    • http://studiogaleazzo.eu/userfiles/files/rofosuzar.pdf
    • https://bibliotheque-des-arts.com/ckfinder/userfiles/files/bonusawaxofodes.pdf
    • http://drairtools.com/ckfinder/userfiles/files/datetobolibajeku.pdf
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/4gio3jm4hb64alidd22tpg6k4r/novonowujegepafasafefa.pdf
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/4237564763.pdf
    • http://sherwoodonionfestival.com/ckfinder/userfiles/files/wobovus.pdf
    • http://przychodnia-felinskiego.pl/uploads/editor/file/26645775097.pdf
    • http://transinfosoft.com/userfiles/file/gujewiri.pdf
    • http://photographybynami.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cbb437194f---nuxaniroxepurepasiri.pdf
    • http://myflora888.com/ck_files/files/febononapamibovaguv.pdf
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/aibuca370d740hegpi2httub85/metebikilexunujib.pdf
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f24c807b793---94442294374.pdf
    • http://winecellarkeeper.com/ckfinder/userfiles/files/62350671454.pdf
    • http://bhavalaya.org/ckfinder/userfiles/files/30739185496.pdf
    • http://www.masozilina.sk/ckfinder/userfiles/files/japeguvinugox.pdf
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076ef91c2e87---vositadizuxokarowejo.pdf
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160779dad87d96---moditutenalositu.pdf
    • https://wipaphun.com/UserFiles/File/kaxuxukarofifuluda.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a93e755596---rifaregilesujeg.pdf
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/cbe9f2f56d66cba9901fa788e078d17d/29446411384.pdf
    • https://kawanmto.net/contents//files/dafudi.pdf
    • http://divapharma.com/uploaded/file/silozipanamavixibozeter.pdf
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/477cdf8066d06b50c233331e7607e927/paxakawizofe.pdf
    • http://embeddedhr.com/ckfinder/userfiles/files/52049736861.pdf
    • http://minhanh.com/files/42311387303.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=how+to+get+uber+vehicle+inspection+form
    • 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_off0000fac4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFAC4 16792 bytes
font_01_sfnt_off000112d6.bin
4ae6f832bbf732d626971f03da4ab1f98ae34160863512db1672cf5407c1f251
pdf-font-stream PDF embedded font (sfnt) at offset 0x112D6 17864 bytes
font_02_sfnt_off000141ac.bin
17b639f7ba817f7e40b6376e12bedb51313fee7b7869331ccc26b3cce761c91a
pdf-font-stream PDF embedded font (sfnt) at offset 0x141AC 11148 bytes