Malicious PDF — malware analysis report

Static analysis result for SHA-256 c05845b06fff6cf0…

MALICIOUS

PDF

81.9 KB Created: 2021-09-20 16:01:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 6c5873970f16e341de1d651c8af5225c SHA-1: f8c8ffe82650764e0e6dc913fbf2cf693ef0faf3 SHA-256: c05845b06fff6cf09667ce2f89fe994e10380f9414ee23b125682d24bc651aa8
134 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The sample is a PDF file containing embedded JavaScript, which is a common technique for executing malicious code. The PDF also contains numerous external URIs pointing to various domains, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or delivering a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://queure.ru/uplcv?utm_term=free+convert+pdf+to+excel+offline PDF link annotation
    • http://drentmedischadvies.nl/uploads/files/lazaxoxisepopezozi.pdfIn PDF document text
    • https://pfollowers.com/ci/userfiles/files/75106106111.pdfIn PDF document text
    • https://santa.sg/images/users/00000000/files/20130296323.pdfIn PDF document text
    • http://lexus-custom.com/js/upload/files/zuwolizifaze.pdfIn PDF document text
    • https://learnrkb.jugalbandiresearch.com/ckfinder/userfiles/files/84379575444.pdfIn PDF document text
    • http://atomicattack.com/atomic/fckimages/file/mofixajikutenidisovisabi.pdfIn PDF document text
    • http://zjhywt.com/images/upload/File/wugiragunesi.pdfIn PDF document text
    • http://bogaarchitetti.it/userfiles/files/vidut.pdfIn PDF document text
    • https://kalashad.com/userfiles/file/80588452713.pdfIn PDF document text
    • http://akademia-jedenastka.pl/zdjecia/fck/file/buvev.pdfIn PDF document text
    • https://ou-ravda.com/ckfinder/userfiles/files/peposolosazaluvofop.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613c01713db43---42985162671.pdfIn PDF document text
    • http://thebrownbag.vn/upload/files/sedazapenilozot.pdfIn PDF document text
    • http://compow.net/ckfinder/userfiles/files/setunupekeku.pdfIn PDF document text
    • https://nezrenweb.com/calisma2/files/uploads/5669454107.pdfIn PDF document text
    • https://binarbaidrealestate.com/public_html/userfiles/file/wujajugewugujiroxepi.pdfIn PDF document text
    • http://ohxto.com/uploaded_files/userfiles/files/71621951760.pdfIn PDF document text
    • https://shiokuda2.com/contents/files/zaridowisepovetegadunu.pdfIn PDF document text
    • http://hotelclinton.it/userfiles/files/katofapen.pdfIn PDF document text
    • https://ichibaninfotech.com/ckfinder/userfiles/files/mogogaseje.pdfIn PDF document text
    • https://lmbri.com/WYSIWYGImage/file/63887366139.pdfIn PDF document text
    • http://fitsiluet.cz/data/file/fixunugadax.pdfIn PDF document text
    • http://phutunggiahungoto.com/uploads/files/luxixebam.pdfIn PDF document text
    • http://idrogastermoclima.it/Utentifile/FCKPage/file/ribeg.pdfIn PDF document text
    • http://osoboebludo.com/ckfinder/userfiles/files/losurodegufigusinazowuxir.pdfIn PDF document text
    • http://kaizousha.com/js/upload/files/69055692157.pdfIn PDF document text
    • 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_off0000dd53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD53 17320 bytes
SHA-256: ecf1b45c5d36c3a1bcc355982b58dd597cd6639b33bbc06adff1d0beb84742c4
font_01_sfnt_off000109e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109E7 10428 bytes
SHA-256: 00349c5f1c90c35f6c188946835acf72d85c14886609dc6a709c54ca02bbd00c
font_02_sfnt_off000121a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121A0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1