Malicious PDF — malware analysis report

Static analysis result for SHA-256 71d066313b84df6b…

MALICIOUS

PDF

80.2 KB Created: 2021-09-13 00:32:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a698b6772ed80cc8c279d1dec2160ae1 SHA-1: 44deece285e49276bb98bfac7b6bc72ce098f0de SHA-256: 71d066313b84df6bc443979be461ae948d487a2b77d010858c206cf2b13779c7
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The use of external links and compromised hosting aligns with techniques used to obscure the ultimate destination and evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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
  • 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://greatwalledmond.com/ckfinder/userfiles/files/63635973273.pdf
    • http://munnarinfo.in/userfiles/file/dodegubexexevewiv.pdf
    • http://lungshingcentre.com/userfiles/68480507705.pdf
    • http://nissanotogovap.net/uploads/images/files/rovijiburugomux.pdf
    • http://opuspoint.com/ckfinder/userfiles/files/83850656768.pdf
    • http://angelofthewinds.net/ckfinder/userfiles/files/dejazake.pdf
    • http://hondatayho.top/img-ngocbao/files/sexuneju.pdf
    • http://fairfresh.net/assets/admin/ckeditorimage/files/19948785916.pdf
    • https://unitedfightalliance.com/ckfinder/userfiles/files/jekidomunipupoxes.pdf
    • http://xn--2osv9pt2jfpt.com/uploadfiles/files/lapuweza.pdf
    • https://ncsccalgary.com/userfiles/files/bixojezube.pdf
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/c48706b3c9ef62a4b90fbfa58a93848b/nuvotakudifibage.pdf
    • http://express-service-auto.fr/ckeditor/ckfinder/userfiles/files/73958779994.pdf
    • https://webkapper.nl/ckfinder/userfiles/files/16526490338.pdf
    • https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/7fbf16351dcc2feed83ca123d20e0581/zedinirozuwalonavovapaz.pdf
    • http://dwornawodzie.pl/userfiles/file/21891582516.pdf
    • http://www.look4job.gr/images/_user_na/file/40542967859.pdf
    • https://e-tta.com/app/webroot/userfiles/files/xebafemo.pdf
    • https://kocarbonag.com/luutru/files/58304360966.pdf
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/81e00f0310c5c5e024b9a5eb7c2a88eb/morekilererovo.pdf
    • https://aiaciran.org/cache/fck_files/file/21782243400.pdf
    • https://karatenarrewarren.com.au/ckfinder/userfiles/files/77779928819.pdf
    • http://www.ondebiz.com/userfiles/file/dokisiziganurebag.pdf
    • http://jolanyee.com/upload/files/202109041603225342.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=hill+climb+racing+full+money
    • 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_off0000d663.bin
aafb5327ec34d4a475e5aa24b8b9c3b07a2e0eececb8b99f4d917b54a7a82d10
pdf-font-stream PDF embedded font (sfnt) at offset 0xD663 17196 bytes
font_01_sfnt_off00010306.bin
3f10165cf44c84b5814cb431c91c6f52d5e1c1ad072b16f7d04b3100de52e1d5
pdf-font-stream PDF embedded font (sfnt) at offset 0x10306 10756 bytes
font_02_sfnt_off00011bb4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11BB4 16792 bytes