Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a802c5ea2b56e88…

MALICIOUS

PDF

91.0 KB Created: 2021-07-01 19:44:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cc5204877fdd32ac823f2df2dbe88432 SHA-1: 7137f6da9edaddf4caa947bd661ae2862e684aae SHA-256: 4a802c5ea2b56e88dffff654423e1076b93953bc849153601228cb663a668f13
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to host malicious content or redirect to phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 https://medvor.ru/uplcv?utm_term=russian+mom+abused
    • https://asiabiru.com/contents//files/68061713224.pdf
    • http://www.makattakasinti.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c942b02068---xurigemozadozosiwowipe.pdf
    • https://luyenthitoeic.info/userfiles/file/53586993017.pdf
    • http://carroll1975.com/clients/4/4e/4e2b018d07aaa5a30c3e4fca1c7a8df7/File/sexemisijorularalogen.pdf
    • http://scbczy.cn/up_files/file/20210622_142331.pdf
    • http://daiichihr.com/uploads/news_file/45211239876.pdf
    • https://webornate.com/viking1/uploads/files/82045428302.pdf
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607fce4976860---tojobegusaguvijefoxu.pdf
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/95994ad9af409e21e283b8799abee307/rukorawikatumamuradun.pdf
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/16bfc240fa6a32975d2c20d5c35e4509/kudidun.pdf
    • https://gikguamerica.com/userfiles/file/pabakarezog.pdf
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606cba734635d---votesatitelezad.pdf
    • http://shmountaineering.co.uk/wp-content/plugins/super-forms/uploads/php/files/7c8h6fs8m33qlpesj2v915npr7/fulurigalonutivafurerero.pdf
    • http://szsahsh.com/uploads/files/46812997518.pdf
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160ab85cd8e128---16913859933.pdf
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bf4fb98eefe---96365447915.pdf
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc607b6def7---86325852004.pdf
    • http://com123.vn/uploads/file/lefajebuwikejopijar.pdf
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/tgu6uuq2kqo91sj4ngb5sat1ok/fuviturobekiki.pdf
    • https://tomas-music.com/contents//files/dipomasagodak.pdf
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/160d5a2d645f47---74005208981.pdf
    • http://bortran.com/upload/image/file/20210608011829.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c00482b2fbf---vezowizitofak.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_off000103ce.bin
909ab3b9f4a18c1b94c9bc01f107334aef6ed8e60e6d9501c86890bac9cbe18c
pdf-font-stream PDF embedded font (sfnt) at offset 0x103CE 16892 bytes
font_01_sfnt_off00012f7f.bin
4f8651a1868e3add3b922938557def960e9fc3daff252f7f06c1cf5f7d18cced
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F7F 10448 bytes
font_02_sfnt_off00014724.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14724 16792 bytes