Malicious PDF — malware analysis report

Static analysis result for SHA-256 af35398e961ca1cb…

MALICIOUS

PDF

76.9 KB Created: 2021-06-26 03:18:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 613fa3e166501e8cad1398ddc43bb2dc SHA-1: f25143c571089b75f74c633091ba8d55023df0ab SHA-256: af35398e961ca1cb0e78cc9b952494d7ca3c6330307fc80f2f8ac142330748e9
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, suggesting a link farm designed to lure users to malicious content. ClamAV and ML classifiers confirm its malicious nature, classifying it as a phishing trojan. The presence of multiple distinct hosts and the use of UTM parameters indicate an attempt to obscure the final destination and potentially track user engagement.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://asfus.net/virgsurv/userfiles/file/59199947435.pdf
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607eb36e52e3e---kojimunotugum.pdf
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609278c7ab465---29462053352.pdf
    • https://www.letspassdriving.co.uk/wp-content/plugins/super-forms/uploads/php/files/cj8vamfohodnt8ns70am943or3/vaxujojolufifisavavofob.pdf
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/1606f46ae74371---52915241885.pdf
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/f456b39c3d14dfaa96094d8697b1ef3b/45344665746.pdf
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/160bd3b60208b5---28263496658.pdf
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/b8931fd05fe6df4f62c69bb7e6ec06da/dekogusolotitenomeroj.pdf
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/4c4c193cfe782a4e93a04656cd4aa85b/98056234097.pdf
    • http://xn--80aadq3ae7aa5k.xn--p1ai/upload/file/bulomotavupomiguxibowo.pdf
    • http://dxczx.com/ckfinder/userfiles/files/20210610_001209.pdf
    • https://www.tanyadantus.com/wp-content/plugins/super-forms/uploads/php/files/599e5fe3e85f5fc765467137c40f0271/68265628197.pdf
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/b26463066fce2ad5b9e937d7758d915d/76268356413.pdf
    • https://www.sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/16088300cc73fb---20398075906.pdf
    • https://faltprasten12.se/anvandarbilder/70/files/gizatopivejiweloravav.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087ed3832181---xajixapigujazopetigefuli.pdf
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160810428aac63---vemejogojaromesuvozaxife.pdf
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160999bc424876---ninenalape.pdf
    • http://cerezolorente.com/files/cerezolorente/_repo/file/20016945118.pdf
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/2fa6e721840bb64a18144030ba0df375/92840354432.pdf
    • https://ph2020.org/FCKeditor/file/mewijazi.pdf
    • https://nutricount.cz/UserFiles/File/nisovesedex.pdf
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/00a2c5a141199f259b6f54b2d0fa6a60/poxawewiduwat.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=what+date+is+it+tomorrow
    • 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_off0000c7f3.bin
d7acad71f9c7e951f5325c4af384d299b46ee4cd4b4d7f7e3b0f5dedcee4ea5d
pdf-font-stream PDF embedded font (sfnt) at offset 0xC7F3 17196 bytes
font_01_sfnt_off0000f4eb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4EB 16792 bytes
font_02_sfnt_off00010d02.bin
9c4154d4acbbadcf978242a716bda291f4cb7980d7035bb61f61fc54b0da52e3
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D02 10444 bytes