Malicious PDF — malware analysis report

Static analysis result for SHA-256 eab37639ae8d2c7d…

MALICIOUS

PDF

88.8 KB Created: 2021-07-16 19:51:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1b749301d87bb83e8c31059cf341c4d7 SHA-1: 5956008ded754f60ca7f87bf1d1ea3f9144700d4 SHA-256: eab37639ae8d2c7de9e2192974bccfc2c3f1c9b2f27e8c5ba265254f9f3a7d63
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it's a link farm and a browser installation lure. The document body is heavily obfuscated, but the presence of numerous URLs, many hosted on compromised or disposable domains, suggests an attempt to redirect the user to malicious sites. The primary lure is to trick the user into installing a browser extension or update.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://myphamlulanjina.com/upload/files/zalomabev.pdf
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160edf1740b359---65539132638.pdf
    • http://ketoanaca.com/uploads/image/files/32532022122.pdf
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/1455d3563c1d89943d002744eb8658ba/zepidetosanu.pdf
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/aa0a35b8f498a048cada871feeeb084e/puwakuzuz.pdf
    • https://wecareu.net/ckfinder/userfiles/files/38722398643.pdf
    • https://capital-tic.com/upload/ckfinder_temp/files/20210528210904.pdf
    • https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/615caa5af4ec857575621c9d637ecfc4/41592339278.pdf
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607b52978fa48---99145180647.pdf
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084f93e1579f---99105463936.pdf
    • https://thuaphatlaihoanghuy.com/uploads/files/finevumanadezapinat.pdf
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160942470a0816---tuxovigo.pdf
    • http://amandamaitland.com/images/file/wexazekidot.pdf
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/c640d0517a6a3d9691afb6f0dc447f97/38108874685.pdf
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/3e7b6746754369824a88ad5ef8da8c85/jurogok.pdf
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/cdcda4dd777bf37ac0c46af13dd30070/ruxabasodomivitobofabijiv.pdf
    • https://wipaphun.com/UserFiles/File/99271219808.pdf
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb4bfc1e450---dabusalelononipuxobez.pdf
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ab84acacb5c---dazaninudonawakujofewef.pdf
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f2874678b5---83249500125.pdf
    • http://eventcompany.org/clients/e/e3/e30ef11cf4efe639fe6592aa37b9cb94/File/ninapabebivobiganiket.pdf
    • http://phutungquanghieu.com/app/webroot/files/ckfinder/files/muzifume.pdf
    • https://watertorens.nl/userfiles/file/retogag.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=install+chrome+os+on+partition
    • 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_off0000f667.bin
23d7eb21a302470767ced5138765c61d9fd31a5cefc2bce0bc39d673e70e6b21
pdf-font-stream PDF embedded font (sfnt) at offset 0xF667 10592 bytes
font_01_sfnt_off00010e63.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E63 16792 bytes
font_02_sfnt_off00012675.bin
fd271f22e9f55271f0097a8975e576f4877c03e6461f144ec24c271bd0ef2243
pdf-font-stream PDF embedded font (sfnt) at offset 0x12675 17576 bytes