Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8b76726cb2fbb5a…

MALICIOUS

PDF

70.1 KB Created: 2021-09-24 19:13:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8e40239c377dcdc09226d6df4a179537 SHA-1: 3af3affdf171fd91f26963987d09e791350a3bbf SHA-256: b8b76726cb2fbb5a36809b466467b948ff02de23772a9bd4a2b8f5ff4f1f9511
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL findings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://groupekheidri.com/ckfinder/userfiles/files/fizirurivopaporuwaxi.pdf
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/a93a1620a084385cf6691c943a9e786f/majifuzan.pdf
    • https://rsun.pro/admin/ckfinder/userfiles/files/bofepixajemewilot.pdf
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16137b3dc97d79---32426592598.pdf
    • http://pravkniga.ru/files/userfiles/files/sitaromekilu.pdf
    • http://linza-market.ru/upload/files/lagolazojikisopokerazavo.pdf
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/1613ddd21d06af---53544322107.pdf
    • http://iccjsc.com/images/uploads/files/ladij.pdf
    • https://la-klamm.org/userfiles/file/88527852306.pdf
    • http://gzlmjx.com/data/home/bxu2343160066/htdocs/uploadfile/files/15829654818.pdf
    • http://muzycznescyzoryki.pl/userfiles/file/jiferokunokulurozu.pdf
    • http://qdjshg.com/files/file/josogulik.pdf
    • https://thinkglobalcompliance.com/ckfinder/userfiles/files/dawonibumuresunuzekoreg.pdf
    • http://ulv-fogger.es/d/files/19879181805.pdf
    • https://cafemocion.com/userfiles/file/najivekijinupibex.pdf
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147cfd8751d2---wetidakugupulura.pdf
    • https://anitt.in/ckfinder/userfiles/files/mudedakubobusuvajuvis.pdf
    • https://insolite.lu/img/userfiles/files/lapajiwol.pdf
    • http://ipai-bg.eu/img/file/50881181042.pdf
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/nedo50ncggupj7qahh2a4najhd/budufogonudanoxuvutepubu.pdf
    • http://ipayon.com/root/FCKeditor/file/jozizadar.pdf
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/a84346ddaa25f7f84b86555db1777311/53978264882.pdf
    • http://finalbrand.cz/upload/file/18063117761.pdf
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143201bc04f8---39300186533.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=moto+g5+latest+update
    • 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_off0000b435.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB435 16792 bytes
font_01_sfnt_off0000cc47.bin
711b087d40ab0328a0beca5734a7b693067e8483c6b6bf1a084e3f70e0e0a2df
pdf-font-stream PDF embedded font (sfnt) at offset 0xCC47 15036 bytes
font_02_sfnt_off0000f283.bin
29b37f0a993151aa668969be3aa4e17e4dc053d0c147b7239b68ac48bb41ab07
pdf-font-stream PDF embedded font (sfnt) at offset 0xF283 10500 bytes