Malicious PDF — malware analysis report

Static analysis result for SHA-256 904ee8f993ef0eda…

MALICIOUS

PDF

72.7 KB Created: 2021-09-20 06:21:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4874c98a7a65c1c934215161552f682b SHA-1: dfbd369ca94b9ad85c0add3f7dbe525966082040 SHA-256: 904ee8f993ef0edaea1eec264ecc78ee31e4091bbc25b8d252a80110da0cab69
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it functions as a link farm on disposable hosting. The presence of numerous external URLs, many pointing to PDF files, suggests a phishing or malware distribution campaign. Although no scripts were directly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 8

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://irlanc.ru/uplcv?utm_term=black+panther+3d+live+wallpaper
    • http://aexpress.lv/index/images/up/file/80499229381.pdf
    • https://peoplehelppeople.net/uploads/File/83440378972.pdf
    • http://homeloanz.net/images/e/file/44840122849.pdf
    • http://geluidsadviesnederland.nl/ckfinder/userfiles/files/xedemegafelefebuvo.pdf
    • http://patroha.hu/file/77474540629.pdf
    • http://www.tobywells.org/media/fckdir/file/biwafajasop.pdf
    • http://daonshop.com/files/fckeditor/file/xofanenazezuni.pdf
    • http://urbariatprasice.sk/upload/file/54993656376.pdf
    • http://sartor.ru/upload/files/bomudojunege.pdf
    • http://gartenmessebau.de/uploads/files/48686397680.pdf
    • http://reklama-v-sochi.com/ckfinder/userfiles/files/85311865418.pdf
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/u83b9nvnvab2bj5ltg8bha6ve2/dekojogobigoxepune.pdf
    • http://danchrisjewelry.com/userfiles/file/42713258920.pdf
    • https://eledigitalpr.it/allegati/file/venurorotaxudol.pdf
    • https://ajambary.com/userfiles/file/87485083524.pdf
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/b6c378c02c218974f587d6048b61d7f3/99140499660.pdf
    • https://hearing-outlet.com/uploads/files/202109160459206714.pdf
    • https://clearpatth.com/userfiles/file/8675418188.pdf
    • https://hargagila.com/uploads/image/files/67368264379.pdf
    • http://balbu.eu/uploads/news/file/xoxof.pdf
    • http://seamacros.com/upload/file/27780138150.pdf
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/161401879c2d87---11058169858.pdf
    • http://zechnerbau.at/images/content/files/83900275400.pdf
    • https://mk-promotions.com/ckfinder/userfiles/files/fobenunuwaru.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_off0000bb58.bin
ad4db45a08ccb1c1f412cb7aea05fb3f3e6f820bc331dea56d79559726b54066
pdf-font-stream PDF embedded font (sfnt) at offset 0xBB58 10792 bytes
font_01_sfnt_off0000d434.bin
54d890faac2c6c57c351f1618527d18bdba193e5d7e74a8252867c2b88b16a8d
pdf-font-stream PDF embedded font (sfnt) at offset 0xD434 15836 bytes
font_02_sfnt_off0000fcca.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFCCA 16792 bytes