Malicious PDF — malware analysis report

Static analysis result for SHA-256 b91b076f49fba5b4…

MALICIOUS

PDF

90.3 KB Created: 2021-07-12 23:52:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 28f01baa3bb21d19951a6ed362ab527d SHA-1: 6698673eb609dadbc932a05ce1c355500eb56209 SHA-256: b91b076f49fba5b4584a51c34bf59af39f042e106da49e9370867bb9eb669f04
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to numerous compromised WordPress sites, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the presence of external URIs and the nature of the link farm suggest it is designed to redirect users to malicious content, potentially leveraging embedded JavaScript for obfuscation or further redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://chcial.ru/uplcv?utm_term=hitman+blood+money+game+download+for+android
    • https://tennis94.fr/img/pics/files/xaminilobasufufi.pdf
    • https://www.asahinadigital.com/wp-content/plugins/super-forms/uploads/php/files/fmv7lsl2uisdi77j20s7censp5/velokifuvasuz.pdf
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/160a926c98f5fe---10360859884.pdf
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/oh5ct5v3jcn7g863r36se14tk2/38572628961.pdf
    • https://atpl.aero/ckfinder/userfiles/files/58610344314.pdf
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/3dba37ce1054fb46a13ce3b026011eec/zolariwojifupobid.pdf
    • http://mrbossamktown.com/uploads/files/17041728675.pdf
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/280d02a0f7e4de41879fc19d18070e1f/74987081270.pdf
    • http://mtecommerce.it/public/news/file/94461105433.pdf
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/a1824f1a8eac44c5dba94d2cdf2668b0/xagenumomudidopomizu.pdf
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073dfaba1bdf---44032363792.pdf
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c706c9355ac---farofumitemoritilurereg.pdf
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/f3bb058af3b35784d36d74fcccea7e35/44124605566.pdf
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b42e08bd1dd---mudodudelekivev.pdf
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/9496ce192d854471e6b8ed680db2e612/47153927713.pdf
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/881b29478bcaf858d1c2f8a66ddd2125/63677873837.pdf
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608c6d761a355---80805761591.pdf
    • http://thelonerangerfanclub.com/ckfinder/userfiles/files/sozugesukajobaso.pdf
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/htbeja1sd3j2caumiqo3k2m1h7/5573939406.pdf
    • https://airflow-skateboards.com/upload/file/37115227804.pdf
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/5r0g0dt0mn26vse95bcsujns4b/97695139649.pdf
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/ffc0c0afa6479e85180e451c92dd2115/38237997357.pdf
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608629ca44fce---soturomibirawefovab.pdf
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/rusowubelepazesofukudux.pdf
    • https://styliststudios.com/imagesTE/file/70596288492.pdf
    • http://inter-travel.hu/_user/file/vevezobusimaresimabuv.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_off0000feeb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFEEB 16792 bytes
font_01_sfnt_off000116fd.bin
f51eaddcedbcad2705f09e4cefdef97f6b66c257277c2a1caf5ce30e64d77f94
pdf-font-stream PDF embedded font (sfnt) at offset 0x116FD 16852 bytes
font_02_sfnt_off000142cf.bin
53d85245a8e4da1b3da42ab29a435eb7f1b0722520600d7182ab7f8bc05dbf73
pdf-font-stream PDF embedded font (sfnt) at offset 0x142CF 10860 bytes