Malicious PDF — malware analysis report

Static analysis result for SHA-256 a425aea65b24f61d…

MALICIOUS

PDF

72.5 KB Created: 2021-10-04 09:19:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5914ed5b1aad480725affda06aa8733d SHA-1: 8e8bd2f0ed3e814d2b81fe187c253cbb07f1df3c SHA-256: a425aea65b24f61d31c8a4f075270febb607a9fc5517934efda45e8a9d81b6a0
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to disposable hosting or compromised CMS uploads, indicating a link farm or SEO manipulation scheme. ClamAV detected this as Pdf.Phishing.Trojan, and the ML classifier also flagged it as malicious. The presence of multiple external URIs and link farm heuristics strongly suggests a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9915

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://ricarda-allegra.de/userfiles/file/tarevijilagonabazum.pdf
    • http://kubablimel.pl/Image/files/92095202042.pdf
    • http://studiolegalebisantis.it/userfiles/files/95110333350.pdf
    • http://nicolalazzarotto.com/userfiles/files/dosogavetijibedaraz.pdf
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1615a95a8eaf91---75700269104.pdf
    • http://kleinschadenexpert.com/userfiles/file/vefatijitedumuxunurodonix.pdf
    • http://choinka4x4.org/cms/files/file/lerewe.pdf
    • https://suma.ca/upload/editor/file/wiraxow.pdf
    • https://alshamiltrading.com/alshamilfiles/file/rijukevutunulo.pdf
    • http://brilsports.ro/userfiles/file///xiwivuzaf.pdf
    • https://piti.leaddeehub.com/userfiles/files/60361918128.pdf
    • http://gloteckr.com/upload/editor/file/21340444955.pdf
    • http://el-system.jp/uploads/2012/files/jomovapudenugedapozowisa.pdf
    • https://cottingham-group.com/cufiles/files/84022844267.pdf
    • http://himalayakebab.irafbrothers.com/shipinc/userfiles/files/lawokijijinekopedavos.pdf
    • http://kieryk.pl/img/userfiles/file/posufibepel.pdf
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f0c3e59117---24062859937.pdf
    • http://cainghienbinhduong.com/uploads/userfiles/file/wobapufivinadage.pdf
    • https://cli-kh.com/uploads/files/202109301701413276.pdf
    • https://giltmorestukko.hu/ckfinder/userfiles/files/jejojodituzafifutotej.pdf
    • http://fsoa.cn/userfiles/file/56347661383.pdf
    • http://aksaaydinlatma.com/img/editor/image/file/61825768807.pdf
    • https://sdhouse.info/ckfinder/userfiles/files/42184549767.pdf
    • http://geoscan.it/userfiles/files/vapesibitiloxelol.pdf
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16159c1d764e40---rajijenowemavurakodi.pdf
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614e4add7afe5---24397497638.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=asian+slaw+with+ramen+noodles
    • 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_off0000b872.bin
153f3565f643eecf792ba147b1dacae98ed0fbab77f99a75267f3cd0e418ab40
pdf-font-stream PDF embedded font (sfnt) at offset 0xB872 17168 bytes
font_01_sfnt_off0000e410.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE410 16792 bytes
font_02_sfnt_off0000fc27.bin
ec09bca3dc689bc7813fe79aa9dad19ca083557fa39844b094ee02f5bdb0a59d
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC27 10580 bytes