Malicious PDF — malware analysis report

Static analysis result for SHA-256 585414d99eab6e37…

MALICIOUS

PDF

89.3 KB Created: 2021-09-12 00:58:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 0ab0aff514983eb7d5eae871e8e0d3bf SHA-1: 79eb2caf7536a89cc7f3daa024e13dc290aa2064 SHA-256: 585414d99eab6e374e27b8d178db8c28b54b584cadcaf36386f2356cf1e91810
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, with heuristics indicating a malformed exploit stream and a link farm structure. The PDF contains numerous embedded URLs pointing to external sites, suggesting a phishing or content-luring attack. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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 https://chmelo.hu/sites/default/files/file/19505780320.pdf In PDF document text
    • https://ph2020.org/ckfinder/userfiles/files/44700818908.pdfIn PDF document text
    • https://alansglobalservices.com/ckfinder/userfiles/files/45398663743.pdfIn PDF document text
    • https://alzubidi.com/userfiles/files/tifadudekiduzixive.pdfIn PDF document text
    • https://albizy.com/ckfinder/userfiles/files/53611710638.pdfIn PDF document text
    • http://www.kingsmen-cmti.com/upload/files/73260052393.pdfIn PDF document text
    • http://arniestribu.com/campannas/file/rojatuzesusamapizofo.pdfIn PDF document text
    • http://tottazo.com/userfiles/file/rinomexog.pdfIn PDF document text
    • http://elesi.eu/fichiers/files/92237529581.pdfIn PDF document text
    • http://gibisch.org/files/files/52856001797.pdfIn PDF document text
    • https://www.adoz.cz/ckfinder/userfiles/files/punigatujemudofomimijakib.pdfIn PDF document text
    • https://angelsolutions.ro/ckeditor/ckfinder/userfiles/files/watuxunopuwipifaroped.pdfIn PDF document text
    • http://emons-verlag.net/testarea/cwsCMSlight/media/files/wukojitufuxunezogek.pdfIn PDF document text
    • http://www.hgbehringer.de/img/files/files/lopexajaxakodojasonozafi.pdfIn PDF document text
    • http://sity-luxe.ru/userfiles/file/20285004998.pdfIn PDF document text
    • https://keluargamimpi2.com/contents/files/rijelivi.pdfIn PDF document text
    • https://ensegun2.com/ckfinder/userfiles/files/dufatiwoxowadetulimiv.pdfIn PDF document text
    • http://m2m2design.com/userfiles/81470431495.pdfIn PDF document text
    • http://enewind.com/pliki/file/66875933221.pdfIn PDF document text
    • https://pellevah.com/upload/files/wuxoguvig.pdfIn PDF document text
    • https://e-casainteligenta.ro/userfiles/file/94908874940.pdfIn PDF document text
    • http://ayurveda-shiatsu-nice.com/upload/files/63873714019.pdfIn PDF document text
    • http://maryalo.com/userData/board/file/76149588636.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=123movies+free+watch+moviesPDF link annotation
    • http://cluster006.ovh.net/~greeters/namur/ckfinder/userfiles/files/pixavuto.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_off0000f8d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8D2 17596 bytes
SHA-256: 4669b8ae6c40bd2611f7ccf435f123753381c4446713596064d1addfe9e236f2
font_01_sfnt_off00012618.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12618 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013e2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E2F 10852 bytes
SHA-256: fb339b7afffd7a6415a91fb7f46ce0cc8e6585faa0e8585614de5ec5e6a5acd2