Malicious PDF — malware analysis report

Static analysis result for SHA-256 252ef15c5e1cb5fc…

MALICIOUS

PDF

85.7 KB Created: 2021-09-08 01:30:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6d42584bb5926130d7cefd3b35748bb6 SHA-1: ee54423c201394a60d8fde143e877c9ff1b145e3 SHA-256: 252ef15c5e1cb5fc44c4bc85b7479ab64dfa16871266a875ccb62d57ee128269
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection. It functions as a link farm, directing users to numerous external websites, several of which are hosted on compromised CMS platforms or disposable domains. The embedded URLs suggest an attempt to lead users to phishing or malware distribution sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://inwebjor.ru/uplcv?utm_term=communication+skills+worksheets+for+couples
    • http://americasbestmanassas.com/uploads/files/rigotebasedosikaxubomev.pdf
    • http://tischlerei-schlusche.de/sites/default/files/file/7667986756.pdf
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/3t3rj466f68of2uh96gdhst180/33945672150.pdf
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/1ccf5eb5a144f6c1866cd8e264264ab7/7737986566.pdf
    • http://zulassungsservice4you.de/bilder/file/nadobowibedipox.pdf
    • http://futuralagoparking.eu/userfiles/files/43413183141.pdf
    • http://firesecurity.sk/userfiles/file/satujifawonabodexanaf.pdf
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2714bd8b09---wanineku.pdf
    • http://zulaikhatextile.com/userfiles/files/vonurivefifowetajasuxuzos.pdf
    • http://imhyuk.com/imhyukeditor/userfile/file/78825139700.pdf
    • https://fa-vietnam.com/webroot/img/files/dorevabipiwedavug.pdf
    • http://fatamorgana.fr/uploads/assets/file/95204476725.pdf
    • http://nickels.design/ckfinder/userfiles/files/zesunanekotirubutesag.pdf
    • https://thuaphatlaihoanghuy.com/uploads/files/gigimiderexaxatewezusid.pdf
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160742b37de302---98562145730.pdf
    • http://cmsrecuperocrediti.it/images/file/98895491886.pdf
    • https://carparts-fixture.com/file/file/wubijumifizibasitovuk.pdf
    • http://peak-experience-europe.com/images/blog/file/51131545204.pdf
    • https://serihosting.com/calisma2/files/uploads/50941886569.pdf
    • http://matras-devison.com/upload/file/vowejezuruzopisaki.pdf
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/b915ac029135fcf10b2e91797025f9ee/dokepori.pdf
    • https://digicpictures.com/downloads/88563103945.pdf
    • http://landia-print.com/pdir/file/59080567009.pdf
    • https://www.tratedu.net/ssss2018/assets/143ad273/ckfinder/core/connector/php/upload/userfiles/files/4007ae604fb6b68f15f237a213e8999d.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_off0000eb1a.bin
958cac803a7384c0553f4d2b19ffc72c765f36a5df3b0ae54bef3aa8981bbec4
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB1A 17288 bytes
font_01_sfnt_off00011753.bin
9d0978483c2226c4c2ea033d277d2ce5e87821485462374d10f8a640fd297f08
pdf-font-stream PDF embedded font (sfnt) at offset 0x11753 11056 bytes
font_02_sfnt_off000130f6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x130F6 16792 bytes