Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b3be12a0ecbcf51…

MALICIOUS

PDF

87.8 KB Created: 2021-07-27 18:13:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6a48234d1c4eb221d3a421240899a44d SHA-1: 8b3825312fd55893f1a9e1240b973358b9671adb SHA-256: 7b3be12a0ecbcf51b8b87b406a11c6d184a07616f10fd4874304cd471449e169
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to websites hosted on compromised or disposable domains, indicating a link farm designed to lure users to malicious sites. ClamAV and ML classifiers identified this PDF as malicious, specifically flagging it as a phishing trojan. The presence of multiple distinct hosts and the use of 'utm_term' parameters suggest an attempt to obscure the true destination and potentially leverage SEO tactics for distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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 http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1f44bd3cc5---39540286952.pdf
    • http://koslita.eu/ckfinder/userfiles/files/lutenudifufowananinulax.pdf
    • http://smit-electronic.hr/upload/datoteke/meganalosikiwekajaxisidav.pdf
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/dabff7b08af67347d483db26971fbbb3/13140987019.pdf
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/undf3k44pmblerf3dq79losp6d/35927504462.pdf
    • http://bularz-auto.pl/images/userfiles/file/40212374994.pdf
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/e48b78cff4f13d7ba79bf0bb8a6ee657/70588390842.pdf
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/61v2hujbrljvrkcch8ocgq9ih3/15536320437.pdf
    • http://vhktn.at/images/content/files/46675451444.pdf
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/e6a1a4ae6e02d3c525db441340fa30a0/kefib.pdf
    • https://muratay.nl/userfiles/file/92581201883.pdf
    • https://acrgroup.nl/userfiles/file/somuxuf.pdf
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/18f0a5c49db5859b855d0dd7ada3e8c6/44181953250.pdf
    • http://posekatzahradu.cz/files/file/muvamipetafesosamatijepo.pdf
    • http://www.motionmantra.com/userfiles/files/76806075568.pdf
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160d48a439c279---40561288114.pdf
    • http://valdhans.cz/userfiles/file/76775653974.pdf
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608430a826a30---45961054575.pdf
    • https://sfeerweter.nl/userfiles/files/sekuzedimarefijobakizuvug.pdf
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c153f8f5d4---repazurazolewupunomage.pdf
    • http://atel-j.nl/uploads/files/fixopimegolifak.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=ejercicios+distribuci%C3%B3n+binomial+2+bachillerato+pdf+resueltos
    • 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_off0000ec02.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC02 16792 bytes
font_01_sfnt_off00010419.bin
abff66df23eeaec9691eb8a32ccd305036d905616d8d549f79162e27cb4043c9
pdf-font-stream PDF embedded font (sfnt) at offset 0x10419 11496 bytes
font_02_sfnt_off00011e9a.bin
b840872e076249342b80cf13d3f66f615fcd5ef94e6233cd3f289f6ff948ab37
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E9A 18500 bytes