Malicious PDF — malware analysis report

Static analysis result for SHA-256 19729e998d9d3caf…

MALICIOUS

PDF

82.0 KB Created: 2021-09-10 10:10:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b7ad89af2a01c4bf50b383cc10acab42 SHA-1: 9e1f7b8aaaf9e0d3203acaced1bd5077ae401248 SHA-256: 19729e998d9d3cafa8978f9e2ea0fd8ccfad7b86910f86206c00d08b82e78e60
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that form a link farm, with several pointing to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically phishing. The presence of multiple external URIs and link farm heuristics suggests the primary goal is to redirect users to potentially malicious or phishing websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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 https://queure.ru/uplcv?utm_term=aplikasi+catur+untuk+android
    • http://markasib.ru/ckfinder/userfiles/files/rujoxuberixob.pdf
    • http://yhbinternational.com/userfiles/file/11898006064.pdf
    • http://box8websites.com/ckfinder/userfiles/files/83461890577.pdf
    • https://yapluka-services.fr/userfiles/file/gidowisudibimas.pdf
    • http://vallovin.it/userfiles/files/6211744226.pdf
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139fc163fc73---45205992710.pdf
    • https://bbox.ru/images/shared/file/sonevatuvu.pdf
    • http://fantasymusic.it/userfiles/files/vegera.pdf
    • http://xn--80aamwn.xn--p1ai/userfiles/file/juxobetumelunis.pdf
    • http://solar-makernavi.com/ckfinder/userfiles/files/65485396149.pdf
    • https://braintreeclinics.com/app/webroot/img/files/didiluvezumew.pdf
    • http://rlangkhan.com/upload/userfiles/files/xufurizofotikosajo.pdf
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/161395252cbcf6---xukirilodidavex.pdf
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/48688d822970f310d5264095848ed710/75498983654.pdf
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/161312a9c6a681---34515010564.pdf
    • http://matchonusa.com/uploads/files/gedoxufaga.pdf
    • https://fultoys.com/userfiles/sebux.pdf
    • https://educationindiajournal.org/ckfinder/userfiles/files/sixagezatuko.pdf
    • https://khotelmarket.com/FileData/ckfinder/files/20210909_126D7F8583721C98.pdf
    • http://dostrojar.sk/UserFiles/file/59754221558.pdf
    • http://www.neoneophytou.com/ckfinder/userfiles/files/tojalilabolup.pdf
    • https://ketex.com/trcgp/ckfinder/userfiles/files/74701141833.pdf
    • http://ttccid.com/userfiles/files/fonutoma.pdf
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a85ed9373f---10425376509.pdf
    • http://peaceinsrilanka.lk/ckfinder/userfiles/files/danolawarekudutosak.pdf
    • http://ps-chiptuning.hu/userfiles/files/53411816193.pdf
    • https://nieruchomosciprzetargi.pl/files/file/32863423013.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_off0000dd6f.bin
01a3b01cdf049a36d75817a78dbbd561ad1ba3beecb382cdf2e2ad6b7a328dd9
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD6F 10548 bytes
font_01_sfnt_off0000f5a4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5A4 16792 bytes
font_02_sfnt_off00010db6.bin
ad6f07db87ce1705e21e4a1e3f2b773979a74ae75f03d6134a73de16d24439ea
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DB6 16704 bytes