Malicious PDF — malware analysis report

Static analysis result for SHA-256 86d075cb4cfce199…

MALICIOUS

PDF

88.0 KB Created: 2021-07-13 16:50:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4fc2ec7f690b1a91ea924e40e00ea58a SHA-1: 3d598390d231cf3f22045389051e9d10813f8a82 SHA-256: 86d075cb4cfce19957f9770bb5451ead09eb32ae31e3c4c9b172a4aabec0987a
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing to numerous external URLs, many hosted on compromised or disposable domains, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. The presence of multiple compromised CMS upload links further supports the malicious nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://yangs-ns.com/ckfinder/userfiles/files/20210710123702.pdf
    • https://cosmopolitanhotelbg.com/uploads/wysiwyg/files/65462640420.pdf
    • http://www.polni.si/Images/files/fewura.pdf
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbb3bcd69aa---66672241686.pdf
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160795db363bcf---lewetiketomitolidozojejin.pdf
    • http://szpital-sulecin.pl/images/fckfiles/file/fuzipejufigoj.pdf
    • http://barcelonasixtytwo.com/userfiles/file/95799248412.pdf
    • http://xn----otbbfbbknchz.xn--p1ai/sadm_files/gujifu.pdf
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/296d0f264e55e0fcd6bf3c77d8ec7a55/gewupetulekoretesi.pdf
    • https://yssnewlessons.org/UserFilesTwo/file/rigudot.pdf
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/sebff4gagbdqcv5k15djcfbk41/vazugumameduxafexikifobof.pdf
    • http://tourbusan.net/FileData/ckfinder/files/20210618_E8029F8F6A1D7FA9.pdf
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a0c23aaac1e---modebitu.pdf
    • https://techson-cctv.com/upload/file/413638986.pdf
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160e5b743bf28a---79995544725.pdf
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/926e8dcb10988b6652653683ecd21e9a/tepixado.pdf
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608002db54b62---1379311616.pdf
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/126ac80e4e5b09b457e575a6d8051d37/1491390701.pdf
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/16096b56d848f4---nuzanudiwulunozab.pdf
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/16086bd988eb12---tuwelora.pdf
    • http://dogable.de/userfiles/file/96004660812.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=can+you+block+someone+in+a+group+chat
    • 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_off0000f4a6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4A6 16792 bytes
font_01_sfnt_off00010cb8.bin
141ba6a3cc3139691ae7efe38120e2e1c3863073d47fed8e1e9c645b63fc9963
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CB8 16960 bytes
font_02_sfnt_off000138e4.bin
14c865e2e37b2b70491c2fd2fa16db73cca9d85264f2d2a0bb7cd5066544c900
pdf-font-stream PDF embedded font (sfnt) at offset 0x138E4 11296 bytes