Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3c5921e08eb8946…

MALICIOUS

PDF

101.7 KB Created: 2021-07-01 19:11:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fa58c9d671d67ce78b546df537b58cb4 SHA-1: 27f142dabdd5c3676821917c1d6386f4f8ae70cb SHA-256: b3c5921e08eb8946c7dd4a4139e842a5c2786cf4f130396dce17ea676c41f03c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links pointing to compromised WordPress installations, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple distinct hosts hosting PDF files within form upload directories reinforces the link farm and compromised site indicators.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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 http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160c666309264f---75947650474.pdf
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/9a3p0qkf8mna8co75eofsle0dg/66134989683.pdf
    • http://accessoriesunlimitedinc.net/catalog/file/88862186691.pdf
    • http://fittbike.hu/files/file/jivamuwed.pdf
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a748a49c94f---kunuridowakejeze.pdf
    • http://handbook.hu/upload/page/file/vutoweleloluwijezemov.pdf
    • https://klcmekatronik.com/ckfinder/userfiles/files/48648435209.pdf
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b64faa4fb4---61888119744.pdf
    • https://envomask.com/wp-content/plugins/super-forms/uploads/php/files/5b71857d525d327d9a2dd642ec0bdf91/34707369856.pdf
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b656c9db74a---wawosafizudozel.pdf
    • https://alirezamirmohammadi.com/images/upload/files/8062925296.pdf
    • http://jmvlpslimited.com/ci/userfiles/files/wegenodikenaz.pdf
    • https://www.demetagras.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ceac8f383e---9552209023.pdf
    • http://bowlingkillers.com/imgdb/files/kosefoket.pdf
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/52d28174bdf61d9a41ae77b5dd4020e3/36015481977.pdf
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097822ee64bd---73680450085.pdf
    • http://meteosputnik.ru/userfiles/file/22358109210.pdf
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160860a117f256---7322982478.pdf
    • http://sxhk365.com/uploads/file///runisugozapotexexo.pdf
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c8867a08435---fowudiged.pdf
    • https://cwlighting.com/wp-content/plugins/super-forms/uploads/php/files/3412d7142cd65d6b53e17bac57fb83f1/vitagorupogaxiwep.pdf
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/mem2so1dpc7p2s6j0eg8s2s8ja/kabisoxonewewefedamifulim.pdf
    • http://pizzeria-millemiglia.de/app/webroot/img/editor/file/81668066260.pdf
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085a7f167de3---dozex.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=catriona+grey+miss+universe+answer
    • 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_off000124f5.bin
1306b3f0f86eed36e39985b38ef79c4d7f4e7b887b539556764a67b2ed3d234d
pdf-font-stream PDF embedded font (sfnt) at offset 0x124F5 10800 bytes
font_01_sfnt_off00013df2.bin
1b1d211d0c4346dfb094e6c70a1b83243a5e8d9dfc1d7a0a3fa1d82140b6ccd0
pdf-font-stream PDF embedded font (sfnt) at offset 0x13DF2 19084 bytes
font_02_sfnt_off00016f99.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x16F99 16792 bytes