Malicious PDF — malware analysis report

Static analysis result for SHA-256 53df474bb87ba783…

MALICIOUS

PDF

76.7 KB Created: 2021-07-31 06:55:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9c36f84de96cdfb06581f28197a027df SHA-1: 6d606cdda9a8a570df3c1d75c141446c64edcab6 SHA-256: 53df474bb87ba7836789ff02800a9840502ed2409f0b12878339132898b7b4d1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to numerous external URLs hosted on compromised CMS uploads and disposable domains, which is a common tactic for phishing or distributing further malware. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://finpacecuador.com/userfiles/file/jelanus.pdf
    • https://allcreaturesinc.com/files/files/pixiwima.pdf
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16095733847a94---17747996340.pdf
    • http://immodraft.nrw/images/architekten_agentur_images_/file/32521807901.pdf
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/158f9ba3940bed75a03b703dc52994e2/56299190100.pdf
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/16091019a83464---62817203356.pdf
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/39adc59cef850ac89b238b0aed478235/16812012551.pdf
    • http://indyztyle.com/ckfinder/userfiles/files/xezimeduxewened.pdf
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607d9f03ee523---rijax.pdf
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d667dbe2ec8---genobafojujo.pdf
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608350cf4fa0d---xalopipafogepogafizun.pdf
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098f0830cfe0---31111061824.pdf
    • http://morard-mcf.fr/data/Files/bilolituzojon.pdf
    • https://purevdavaa.mn/uploads/ckfinder/files/16777734120.pdf
    • https://cvsc.co/userfiles/file/28116800529.pdf
    • http://hutbephottaihaiphong24h.com/upload/files/nobidudumuxavazijavowevez.pdf
    • http://www.toptehnik.si/images/wirawakutet.pdf
    • https://www.enterpriselighting.com/wp-content/plugins/super-forms/uploads/php/files/96ca3d0ae0f6076c3004defd6c54cbf9/biwojarerilitejusese.pdf
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607615a975b93---jupapovasomigurid.pdf
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f1d2ec466db---bululuwenudev.pdf
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/515d7a7837a7609bf8b39fe2c74fc9d1/mabetil.pdf
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f9c578063ff---lafonubasinaberaberizuvi.pdf
    • https://parklanehotel.asia/userfiles/file/33001872371.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=minecraft+pe+mods+download+pc
    • 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_off0000c671.bin
5bb2fcbf0f29749a75a754f90376207d8f4024b7385df54880c5c05e0cfd2990
pdf-font-stream PDF embedded font (sfnt) at offset 0xC671 17744 bytes
font_01_sfnt_off0000f240.bin
f33e95d01513b5bf90b7a8f85f07ec456fdeac93dcdd68abb2235f93ffa1d0b3
pdf-font-stream PDF embedded font (sfnt) at offset 0xF240 10860 bytes
font_02_sfnt_off00010b62.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B62 16792 bytes