Malicious PDF — malware analysis report

Static analysis result for SHA-256 d99f1989eff54eb3…

MALICIOUS

PDF

83.9 KB Created: 2021-09-19 05:23:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 141e06838136c2613fef8ec488464c77 SHA-1: 3984c19e5eef311e68580c8198d49230e449be2c SHA-256: d99f1989eff54eb3771be6ffc0ea81c6f3f35219c99e51864ba5a2a30a4df8fe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to other PDF files hosted on various domains, some of which are associated with compromised CMS uploads. The primary purpose appears to be directing users to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://aokisuper.com/ckfinder/userfiles/files/pesapubevebaw.pdf
    • http://gamax-moto.cz/data/dokumenty/68298108585.pdf
    • http://winteringlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/vosozebixupej.pdf
    • http://logisticsnetworks.net/ckfinder/userfiles/files/97276974755.pdf
    • http://massvt.sk/editor_uploads/system/files/7159643857.pdf
    • http://baodieptailor.com/uploads/2021-09-02/images/files/butameribokidezozo.pdf
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/603084297357fecdcb931afea7fa3d86/73568303817.pdf
    • http://kbautotech.com/board/datafiles/imagefile/69920627057.pdf
    • http://mentor-tutor.com/newGroserLikeProject/uploads/files/nolowajowo.pdf
    • http://thegioichuyendong.info/app/webroot/upload/files/28480998661.pdf
    • http://ruresept.ru/files/file/32348428333.pdf
    • https://muzpony.de/obrazki/file/77600630093.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/u1vgki3hbev9avajl7j9rfogr6/86339782568.pdf
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/161413d1db5d3c---nubepanuxurap.pdf
    • https://campermagazine.tv/public/file/75424875268.pdf
    • http://thecargonepal.com/userfiles/file/77505154048.pdf
    • http://karinameal.com/imgdish/files/15782901956.pdf
    • https://bbox.ru/images/shared/file/18829975587.pdf
    • http://fairbank-ia.org/admin/ckfinder/userfiles/files/pogureboburos.pdf
    • http://owv-sad.de/userfiles/files/1920015991.pdf
    • http://sirindhorn.net/upload/File/pogijarasogigesoji.pdf
    • https://ises.smithpressautomation.com/phpsites/vertical_living/uploads/file/darabike.pdf
    • https://abhrian.com/userfiles/files/3271856584.pdf
    • https://giaynangchieucao.com/userfiles/file/28901193704.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=android+on+the+raspberry+pi
    • 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_off0000e1c2.bin
7ace7229fdbd40fea4935505bc1ff3a5050412c306f74921673d1fbab1ec1648
pdf-font-stream PDF embedded font (sfnt) at offset 0xE1C2 10680 bytes
font_01_sfnt_off0000f9f8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9F8 16792 bytes
font_02_sfnt_off0001120a.bin
96761162732610f97fdc3a6ce5b3e4a4322a6ef42904eb0dc2fc900b17da7000
pdf-font-stream PDF embedded font (sfnt) at offset 0x1120A 18512 bytes