Malicious PDF — malware analysis report

Static analysis result for SHA-256 85830e00ffd11a88…

MALICIOUS

PDF

78.8 KB Created: 2021-09-03 08:11:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: eed8a9ea6f823141899ddd1593f07aeb SHA-1: 0db792d818988de8b70a34db39c00904bff826b0 SHA-256: 85830e00ffd11a8803fc75444cad5d5a5e35c1cbe6826c793e0a5a7da0568a95
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous URLs, several of which are hosted on compromised WordPress sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple external URIs and link farm heuristics supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://levakov132.ru/userfiles/file/7282541284.pdf In PDF document text
    • https://simplehome.ro/ckfinder/userfiles/files/55557921300.pdfIn PDF document text
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/cad750b9f83508d66c2b2dc8df9ac796/3342624354.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/523eeddd9646093ea2adff375520d28f/zepapejekutejofokaberu.pdfIn PDF document text
    • http://rana-international.com/userfiles/files/81538897355.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160adffec6e4d1---7676348574.pdfIn PDF document text
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/160b42bf99feb1---67032761612.pdfIn PDF document text
    • http://zxpgw.com/userfiles/file/bodire.pdfIn PDF document text
    • http://ellenia3.eu/userfiles/files/95885636727.pdfIn PDF document text
    • http://relaxzenter.com/uploads/files/lozaletagoge.pdfIn PDF document text
    • http://denkobarbell.com/_upload/files/pajaduxukogorusovaka.pdfIn PDF document text
    • https://fzclicks.com/demo/files/editor/file/buzubusadepejesilebexegaz.pdfIn PDF document text
    • https://pepinieramontana.ro/ckfinder/userfiles/files/vadojivimedosiwa.pdfIn PDF document text
    • http://boldogelet.hu/media/93269371687.pdfIn PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb651256132---85788522171.pdfIn PDF document text
    • http://www.sas.edu.mn/ckfinder/userfiles/files/50751405424.pdfIn PDF document text
    • http://taiwanglassgroup.cn/userfiles/file/jirupewew.pdfIn PDF document text
    • http://atya.eu/files/file/99647754457.pdfIn PDF document text
    • http://boxerdapolenta.com/cmsimple/images/file/1254437045.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/16121a8dc73247---35400181439.pdfIn PDF document text
    • http://metabolit-plus.ru/files/file/53508474374.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1609a27c59cc06---rusosigilinesakolepad.pdfIn PDF document text
    • http://xn--k1akb4c.xn--p1ai/userfiles/file/69423351634.pdfIn PDF document text
    • http://tischlerei-schlusche.de/sites/default/files/file/lodivupuwotajunexuvasod.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=diabetic+nephropathy+definition+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cdc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDC5 18132 bytes
SHA-256: 42abb3c9c470af628448a061b2fa8cea80f1455b9b4378ebffa2b4bc27d71088
font_01_sfnt_off0000fd08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD08 10756 bytes
SHA-256: 06560ed45559747c1c4553dbc50c0682791f228e07690c69ebdfd792c46aebd0
font_02_sfnt_off00011587.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11587 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1