Malicious PDF — malware analysis report

Static analysis result for SHA-256 478f8bbec21d7389…

MALICIOUS

PDF

88.7 KB Created: 2021-07-06 04:01:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7aa1e38be9cbc17b3157d5ebbc15269e SHA-1: f8b7bc037848aa1642527a04875a4cf3ea61c204 SHA-256: 478f8bbec21d738939b0c021b5755bdda164215b1126c3117d7395a96eed04ad
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites hosting other PDF files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of 'utm_term' parameters in some URLs suggests an attempt to track user engagement with these malicious links.

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=warframe+how+to+rank+up+fast
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c7ad6f4c6ab---tupesivusewugivovod.pdf
    • http://www.asejnrtigers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160887f67b8a73---5713767995.pdf
    • http://ecovn.vn/uploads/news_file/21735509611.pdf
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160849ae6f011d---bisezonefapixitof.pdf
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/n77jcqb2hid9sjac75q1cmqkli/guvuxek.pdf
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160b034bdb2954---piponesugogu.pdf
    • https://proektasis.gr/admin/spaw2/uploads/files/sebitoruz.pdf
    • http://detaycopymatbaa.com/userfiles/file/sufudawet.pdf
    • http://sungsam.net/userData/board/file/pogekumewodusomajalato.pdf
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081a606711bb---xemalewigiba.pdf
    • http://bakoca.hu/files/file/60293699422.pdf
    • http://lumieretvie.com/userfiles/file/rujenawutuzisor.pdf
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/e21r69mq1q440jhmuumae8k6v3/38137070364.pdf
    • http://kup-vino.cz/web/ckfinder/userfiles/files/69045513477.pdf
    • https://grupahatak.pl/admin/_fck_files/file/wisamipinode.pdf
    • http://chinahongji.com/d/files/54296301046.pdf
    • http://frickcontrols.com/uploads/files/nivuzekakixubedunuwixokuw.pdf
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/7035e26f4a18eb6297f50c0f41905c22/xuvovufivinalusoku.pdf
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160737cf20d7de---pedefatijozejis.pdf
    • http://iworking.vn/uploads/files/79627786155.pdf
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c37262e2083---54880449976.pdf
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/826dc888d3d3f974985a7d0ea77d2064/jidogamuwexinomanubogule.pdf
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16075dcaac20bf---82241331894.pdf
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//97471879410.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_off0000f8af.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8AF 16792 bytes
font_01_sfnt_off000110c1.bin
400cac0ad5165a9ed67df7a9bfb1451681c0361c2bde1f73371a0676f6e3b3e3
pdf-font-stream PDF embedded font (sfnt) at offset 0x110C1 16968 bytes
font_02_sfnt_off00013cc3.bin
e12ea0e19683ac3e2fabdee3a3940782061b8d86286ad08917448d07ebd9b908
pdf-font-stream PDF embedded font (sfnt) at offset 0x13CC3 10756 bytes