Malicious PDF — malware analysis report

Static analysis result for SHA-256 c70b3d5d4e4f0380…

MALICIOUS

PDF

79.8 KB Created: 2021-09-22 22:37:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 96a261834099002a1bdafc174d8839fc SHA-1: 251adfc92ca5246408a607720853e4b1b8f41fc3 SHA-256: c70b3d5d4e4f038035c17d0cb0a3ef7b80af8655bc232deed8186f28c40cdc10
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised websites and potentially malicious URLs. The presence of numerous links on disposable hosting and the use of UTM parameters suggest an attempt to distribute malware or conduct phishing attacks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 https://inwebjor.ru/uplcv?utm_term=apk+free+fire+game PDF link annotation
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613ecaaf5ac72---85967747876.pdfIn PDF document text
    • http://ipoz.pl/userfiles/file/41554047422.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/513aee93fa7e61a140123f9d99ac84d3/8522523916.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/1d73af17f41592eb8d48774508d10e13/nopifujekisok.pdfIn PDF document text
    • http://lj-group.cn/upload/files/vifanupenulewaf.pdfIn PDF document text
    • http://dlshixiang.com.cn/ckfinder/userfiles/files/mamawupaw.pdfIn PDF document text
    • http://ks-system.co.uk/ckfinder/userfiles/files/migudokubotudaru.pdfIn PDF document text
    • http://havefuntogether.com/image/upload/File/peniwitete.pdfIn PDF document text
    • https://tttinox.com/upload/userfiles/files/4689922445.pdfIn PDF document text
    • http://smartvoicecom.com/userfiles/jewogobirame.pdfIn PDF document text
    • https://ljlconst.com/admin/images/file/77649157821.pdfIn PDF document text
    • http://conditum.nl/userfiles/file/73002541282.pdfIn PDF document text
    • http://space-edge.com/upload/files/benifanexunevixavoliseki.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/9r3s724tj5qfr3sev5dcpd4gi8/91019124431.pdfIn PDF document text
    • http://cermak-expo.cz/data/files/file/48654114349.pdfIn PDF document text
    • http://print-printonline.com/ckfinder/userfiles/files/51654255553.pdfIn PDF document text
    • http://biblioteka-belzec.pl/upload/files/sanonogatuzuseguzar.pdfIn PDF document text
    • https://feniks9.ru/ckfinder/userfiles/files/mirej.pdfIn PDF document text
    • https://interstudy.net/userfiles/file/giletazimojolomowewane.pdfIn PDF document text
    • https://lenaoyunlar.com/calisma2/files/uploads/15950752225.pdfIn PDF document text
    • http://sake-tori.com/images/library/File/70461949270.pdfIn PDF document text
    • https://tdfstore.it/file/gajexuberonawixalofotek.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_off0000d4ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4CE 10240 bytes
SHA-256: 691949178d1f60382339a3066c3c0bb5b0fb6584ba639a9c64eba262f370cef9
font_01_sfnt_off0000ebd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBD6 17812 bytes
SHA-256: f8a55eff4a6ae7d869bb2db671212c308f7ea3394fc1dbb2a99a0d65eadf1043
font_02_sfnt_off00011a35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A35 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1