Malicious PDF — malware analysis report

Static analysis result for SHA-256 377c251d76b1fe58…

MALICIOUS

PDF

74.0 KB Created: 2021-09-10 12:56:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b5574f0ad3e7730bb6284584e041dcd4 SHA-1: 8bd3b91046fd9d616ef68dc4586f63c5c887e6f4 SHA-256: 377c251d76b1fe585bd7e38db77c21381bdc6e7742279e41e304263821abe341
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. Heuristic analysis revealed it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS uploads. The embedded URLs suggest an attempt to distribute further malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16137236a396bc---rotiwilixeputabag.pdf
    • http://www.weilandensemble.nl/ckfinder/userfiles/files/26084576972.pdf
    • https://universal4shipping.net/userfiles/file/53959962342.pdf
    • https://rpdev.org/ckfinder/userfiles/files/27735129849.pdf
    • http://zh-huaxun.com/uploadfiles/files/20788137740.pdf
    • https://www.studiorosaliabusco.it/ckfinder/userfiles/files/92629342097.pdf
    • http://greenld.com/userfiles/59680146501.pdf
    • http://asvpp.fr/pdf/rewakewakowuva.pdf
    • https://biserica-izvorul-tamaduirii.ro/files/vazorobe.pdf
    • http://thevisionkharj.com/userfiles/files/manevonawoziruxiwul.pdf
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/f1015c570c9cc37f6981ab07cbdf4d8f/44803927266.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/16138f8129942f---98833631772.pdf
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1613612c389393---givetod.pdf
    • http://alisawedding.com/upload/users/files/luminasetapunabofomub.pdf
    • http://strahyi.ru/images/file/27778652469.pdf
    • http://madurastones.com/userfiles/file/lesenoroxanogiki.pdf
    • https://groupunsur1.com/contents/files/dusizexilefemitizewugikin.pdf
    • http://humansharehouse.com/userData/board/file/senabufifafijokowur.pdf
    • https://helices-evra.com/userfiles/file/lixejaxusipi.pdf
    • http://dralituncer.com/userfiles/file/20241397959.pdf
    • https://maintogelonline.bet/contents/files/98251171412.pdf
    • http://www.mariabeckmann.com/fotos/uploads/files/nidojidibe.pdf
    • http://abwgulfport.com/uploads/files/36366804579.pdf
    • https://markmont.eu/editor_uploads/system/files/zunuvexunijurabutobol.pdf
    • http://seasonmediagroup.com/pic/file/livedozisatewakabi.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=pubg+beta+version+1.0+0+download
    • 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_off0000bd8b.bin
67c443b6ceb8d98e79eb8c3d70483ae6e8fda8268409b50f988fe5879ae9fb5d
pdf-font-stream PDF embedded font (sfnt) at offset 0xBD8B 16864 bytes
font_01_sfnt_off0000e8be.bin
1c47c37596cfea29be1a1fabf8a8c36d5b81ffb008270d075f6e7f7ac9c68679
pdf-font-stream PDF embedded font (sfnt) at offset 0xE8BE 11056 bytes
font_02_sfnt_off00010280.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10280 16792 bytes