Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef11635a8213d2f1…

MALICIOUS

PDF

80.1 KB Created: 2021-09-03 09:45:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 853ad881e80defb063f487e4471e4b8d SHA-1: 6b1931a5c388c9939c90fabcb63e9f1ed211fc27 SHA-256: ef11635a8213d2f108a76308c40cb3380967b3e284df3999e5ec26ba40747990
156 Risk Score

Malware Insights

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

The PDF file contains numerous links, many of which point to compromised websites or disposable hosting, indicating a link farm designed to lure users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://techbico.vn/uploads/image/files/1863365858.pdf In PDF document text
    • http://kamennykoberec.eu/editor_uploads/system/files/jujawojabibebafutoza.pdfIn PDF document text
    • http://ankamet.com/userfiles/file/dagazeluruzatuvubulam.pdfIn PDF document text
    • http://jpind.pl/userfiles/file/kodaxexinezemisike.pdfIn PDF document text
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074c0044ef97---koxejela.pdfIn PDF document text
    • http://heydarbaba.org/resimler/files/tizerujeguganiveniwut.pdfIn PDF document text
    • http://studiofapas.it/userfiles/files/63985919593.pdfIn PDF document text
    • https://luxmarketing.agency/wp-content/plugins/super-forms/uploads/php/files/elhbk7h8a9m3pfd3bagcde1gmj/89537437321.pdfIn PDF document text
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/a4nqpsnp3hjv65m4h9okog43ud/19721388312.pdfIn PDF document text
    • http://nfraccon.org/userfiles/file/rojewalatufobimoforadaget.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5cd04715c0---10934695752.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160cccfb14d8a6---bugukefamibumoxaj.pdfIn PDF document text
    • https://congchung7.com/upload/file/nesezujarem.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/6615bc559ff40b3c17ff5cbaac2eb43f/tupedirobomivulisi.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/rjk142i784vcdvk1vpnd5eajb0/lesawinakeguwo.pdfIn PDF document text
    • http://nsfeed.com/_UploadFile/Images/file/bivobixete.pdfIn PDF document text
    • https://andrejc.si/files/file/84981843343.pdfIn PDF document text
    • http://coinproject.com/userfiles/image/file/7123678496.pdfIn PDF document text
    • https://hglobaltourb2c.com/FileData/ckfinder/files/20210623_2DA93C3DE062F342.pdfIn PDF document text
    • http://www.adarshvidhyasankul.org/userfilesfile/jutitin.pdfIn PDF document text
    • http://eprdel.cz/userfiles/file/15264981244.pdfIn PDF document text
    • http://watdoenwevandaag.nl/upload/vuwapilonap.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=s%C4%B1rl%C4%B1+dualar+kitab%C4%B1+pdf+indirPDF 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_off0000d45e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD45E 10524 bytes
SHA-256: 869f378f770bb7592110a14a12275a611a23a82be96907768fc8b97724372ad5
font_01_sfnt_off0000ec17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC17 18564 bytes
SHA-256: 08cb5ae1d4eaba8ebc74251a3d9ee669ac36aebd706222f184f4af58cf1b188e
font_02_sfnt_off000118ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1