Malicious PDF — malware analysis report

Static analysis result for SHA-256 5125d91ad6fb9e6e…

MALICIOUS

PDF

83.7 KB Created: 2021-09-20 11:48:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 08d57000fec3665e69e8fbfe901c5111 SHA-1: 92d00b8acec2dd773b6d59f4287479acfc132f72 SHA-256: 5125d91ad6fb9e6ea8b08487b31b838e56fd153d0439da769b04169e5167b0b1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm pointing to numerous compromised websites, a common tactic for phishing or distributing malware. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is unreadable, but the heuristic firings confirm the presence of external URIs and links to compromised CMS uploads, suggesting a malicious redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://lohoithaiduong.com/uploads/files/zomuxovuwavazepuz.pdf In PDF document text
    • https://nyig.com/files/file/22893591085.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613d182e37777---10002924583.pdfIn PDF document text
    • https://lokmangal.co.in/wp-content/plugins/super-forms/uploads/php/files/9592519a2f484099d3bdda68a832d019/ralomoreg.pdfIn PDF document text
    • http://www.diplomat2014.ru/ckfinder/userfiles/files/32582515032.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/161464637aedc3---vugilozixexenilo.pdfIn PDF document text
    • http://boardmark.com/files/file/58380641869.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132486ff2a5c---sokenedipetek.pdfIn PDF document text
    • https://candica.pl/ckfinder/userfiles/files/23433565916.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/0524bc6b3aef9aa3794ac27d4d53517d/mupoduxomelerosuzunel.pdfIn PDF document text
    • http://glttek.com/userfiles/file/99666989939.pdfIn PDF document text
    • http://tnhmc.com/userfiles/file/wojedoserire.pdfIn PDF document text
    • http://women-for-marriage.com/ckfinder/userfiles/files/guweniligujozi.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/kc7oab0u1gb9h1npg0u2opge02/59415006003.pdfIn PDF document text
    • http://diennuocdanang.com/uploads/image/files/rewibekukidot.pdfIn PDF document text
    • http://nextgenship.net/upload/file/2021090716310157269.pdfIn PDF document text
    • http://yogaschoolofkerala.com/photos/editor/files/4658806670.pdfIn PDF document text
    • http://qdxqw.com/uploadfile/file/69578292726.pdfIn PDF document text
    • https://bokaichenyu.com/upload/files/58775599446.pdfIn PDF document text
    • https://cualuoihoanmy.com/uploads/userfiles/file/66299951277.pdfIn PDF document text
    • http://cjmfgx.morefriendship.com/upload/files/10911155780.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=coloros+game+space+apkPDF 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_off0000e05a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE05A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f871.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF871 10548 bytes
SHA-256: 5b812d261361ded7fc472747fb0a21bab0ba080137206b86cea8a3c703e2ba74
font_02_sfnt_off0001108d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1108D 18544 bytes
SHA-256: 82f0aacfe66fae3b38d97b628e5bf05d5a87a19fdb9889cfa34ce49e827209e8