Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d6c24e657e4fbff…

MALICIOUS

PDF

114.9 KB Created: 2021-07-12 23:04:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-23
MD5: 9bbcf34ff20bcedb93e28859619c700c SHA-1: 7d434fcb4afe06e6555aca25e2c6761a7fd4d5c5 SHA-256: 3d6c24e657e4fbff64cb9345eabafb4011f4cc7f57ee8f3bf0d1a8ccb3f6db23
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9925

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://catamma.ru/uplcv?utm_term=unit+of+spring+constant+is PDF link annotation
    • http://atenngo.com/admin/sites/site/documents/68563590122.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/40910518703.pdfIn PDF document text
    • https://bravo-hk.com/userfiles/file/80234730819.pdfIn PDF document text
    • http://bronia.org/userfiles/file/95891412783.pdfIn PDF document text
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/c5317243dce9d7aeb16c9082ad8d94f7/42192828675.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079f8bf1c450---91659276533.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e01345f3ad1---26707988927.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a3c2518df3f---zufibasuxudasipuz.pdfIn PDF document text
    • http://apcmagon.com/userfiles/11832057316.pdfIn PDF document text
    • http://dangkykinhdoanhkiengiang.com/upload/ck/files/witimomek.pdfIn PDF document text
    • http://thangmayedex.com/webroot/img/files/64795872429.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c84c5d1b17b---fokovusoxog.pdfIn PDF document text
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/cca493d065792aa5b9fe0bd6e190a643/9434509592.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/160a63b609da58---pojolaxawobilopisazusi.pdfIn PDF document text
    • http://win-sonic.com/kida2018/ck_imgs/files/ginekariretik.pdfIn PDF document text
    • http://tamker.hu/userfiles/file/25568149459.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/160877736dd6fc---44183032693.pdfIn PDF document text
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/16b690e1edb405e0c69467acbe049021/30856238537.pdfIn PDF document text
    • https://ilc.ua/wp-content/plugins/super-forms/uploads/php/files/pr6fcsgi6s6kfil3micdaq6bd0/36177011630.pdfIn PDF document text
    • https://certifiedmoversinc.com/wp-content/plugins/super-forms/uploads/php/files/e1bff5569aee03874995e3afc36cfbfc/bofenedurigeriboxuga.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093d0b606557---rifenukam.pdfIn PDF document text
    • http://splogservice.ru/content/file/32482191550.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013eee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13EEE 16304 bytes
SHA-256: 5f54e63e2eb35f864201957d7a8a70814ddc327d8c67f1bf9e4823bcccc1c961
font_01_sfnt_off00015529.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15529 20468 bytes
SHA-256: 6a2ce38ba4bb00a488e69ec7853f8caa83ef74cdaf23d00051d92bbbf450e960
font_02_sfnt_off00018c82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18C82 10484 bytes
SHA-256: 0cf8b16bc1cfe4fcc216ac3f971b1507a6181a5e80c0871d5d5ca89977901647
font_03_sfnt_off0001a480.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A480 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1