Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4c75f8ed08cac15…

MALICIOUS

PDF

88.2 KB Created: 2021-09-13 05:57:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 18d1429e93ac7a5a02257a8f3a2354f7 SHA-1: f588779b0f990520498a5897496c864eb440825f SHA-256: e4c75f8ed08cac15140c69e922c45080f46a679810e466c6671a5d79f750dcf7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with many URLs pointing to potentially compromised websites or disposable hosting. The embedded URLs suggest an attempt to redirect users to external sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://mrcubezpieczenia.pl/app/webroot/media/files/21611067819.pdf
    • http://koszyczarek.pl/userfiles/file/48385196327.pdf
    • https://ngoctraithaibinhduong.com/uploads/news_file/66812427402.pdf
    • http://drxzhang.com/userfiles/file/tomaxunoju.pdf
    • http://landonintergroup.com/ckfinder/userfiles/files/nekubiwokatoza.pdf
    • http://gsemilia.it/userfiles/files/gojatu.pdf
    • http://elverum-revmatiker.no/images/file/woxuj.pdf
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/5e9ea3ca74883e23cba89d4e569d64f7/tijamubux.pdf
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16133c1b5c4fbb---45111747275.pdf
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/r396ldfdqdr4oiep3tqsdqs60o/nozovijikatoxafesurorufi.pdf
    • https://bleikss.com/userfiles/file/bozodogejedav.pdf
    • http://nagyberki.hu/sites/default/files/fck_uploads/file/30116778343.pdf
    • https://danielfelber.ch/userfiles/file/8332817833.pdf
    • http://asijskepotraviny.cz/files/file/94052484392.pdf
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613825947a48d---rugodegebanoburijagogula.pdf
    • http://yenidenyuzlendirme.com/ckfinder/userfiles/files/39782912546.pdf
    • http://nacyc.jp/Upload/file/97110799002.pdf
    • https://avukat.dnsaktif.net/upload/files/falezozoguv.pdf
    • http://zaintik.org/files/galeria/files/kutatataxosisikuxo.pdf
    • http://mistral-paints.cz/userfiles/files/55209623473.pdf
    • https://esterkins.de/ckfinder/userfiles/files/78049290754.pdf
    • http://vncdata.net/app/webroot/uploads/files/77053253546.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=resident+evil+watch+online+movie+free
    • 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_off0000f496.bin
4ecd664823c89da24dfd04a4078fd2b0a4a7c36cf48638e891548227b854dcf7
pdf-font-stream PDF embedded font (sfnt) at offset 0xF496 17740 bytes
font_01_sfnt_off00012217.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12217 16792 bytes
font_02_sfnt_off00013a2e.bin
e88490f00ce01bc11215e7a19649095edd7cb4cbd3ff00893eac7b8b1f7ac46f
pdf-font-stream PDF embedded font (sfnt) at offset 0x13A2E 10936 bytes