Malicious PDF — malware analysis report

Static analysis result for SHA-256 43e27fddef657cd6…

MALICIOUS

PDF

85.0 KB Created: 2021-09-13 10:23:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 3deb3a05352f2f6043c50c86a5798adb SHA-1: d4c4b43b907cd7731739ae29b2a5a9185c77df63 SHA-256: 43e27fddef657cd6b87c37a902277310cea7b4c20c02f602d763f9a0e6b3fcc4
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, with a high heuristic score for ML_NYX_PDF_MALICIOUS. It contains embedded JavaScript, indicating potential for malicious actions. The PDF also functions as a link farm, directing users to numerous external PDF files hosted on various domains, suggesting a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://www.aaar.cat/assets/js/ckfinder/userfiles/files/26955710226.pdf In PDF document text
    • http://www.egymast-segito.hu/uploaded/fck/file/83693607118.pdfIn PDF document text
    • https://all-stage-meditation.tw/uploads/files/6131b7dfb6c94.pdfIn PDF document text
    • http://daphongthuyhueminh.com/uploads/image/files/25065540809.pdfIn PDF document text
    • http://goodtraefarm.com/ckupload/files/zawemuzibopixab.pdfIn PDF document text
    • http://pnc21.com/files/fckeditor/file/747313210613eb13eed88a.pdfIn PDF document text
    • https://dalton-english.com/userfiles/file/5018550810.pdfIn PDF document text
    • http://imailbox.nl/images/uploadedimages/file/20062707215.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/161305f0c337fa---gitenamikurapeg.pdfIn PDF document text
    • http://studioagronomoserragiotto.eu/userfiles/files/68061829668.pdfIn PDF document text
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/9fe32111ca5bd4cd29ab9229798892db/63171412332.pdfIn PDF document text
    • https://0922.sproname.com/files/userfiles/files/69575096676.pdfIn PDF document text
    • http://savvyais.com/userfiles/file/xuwiruwuxebimibelaboje.pdfIn PDF document text
    • https://groupunsur3.com/contents/files/563197942.pdfIn PDF document text
    • http://chulatutoracademy.com/chulatutor/ckfinder/userfiles/files/wevusadedededilujoxus.pdfIn PDF document text
    • https://erdenet.mn/userfiles/file/fojidofobeziratekisepod.pdfIn PDF document text
    • https://tunguoilon.tunhua.vn/ipp/images/uploads/files/sozexabebekedepugux.pdfIn PDF document text
    • http://ohxto.com/uploaded_files/userfiles/files/69161400120.pdfIn PDF document text
    • http://markasib.ru/ckfinder/userfiles/files/65161070962.pdfIn PDF document text
    • https://triosms.com/userfiles/file/31817139761.pdfIn PDF document text
    • https://negaratoto.com/contents/files/puwavekop.pdfIn PDF document text
    • http://studiobonvino.com/userfiles/files/69094463638.pdfIn PDF document text
    • http://jarosi.hu/files/file/62261339505.pdfIn PDF document text
    • https://daulte.ch/ckfinder/userfiles/files/deguniz.pdfIn PDF document text
    • http://advocaatindex.nl/images/uploads/3852481035.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=how+to+download+pictures+from+google+images+on+androidPDF 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_off0000e607.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE607 17652 bytes
SHA-256: ba5ebdc8fd7b0a06bf70f65fa1334e958aa86677ab7fa840eaf5460cbdf71f3b
font_01_sfnt_off000113e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113E0 11140 bytes
SHA-256: 90fcc661b017d5c3fe3e0e5454cc523aecf421852eac910e67d4b412b8fa9046
font_02_sfnt_off00012db4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DB4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1