Malicious PDF — malware analysis report

Static analysis result for SHA-256 e8788070680d95c4…

MALICIOUS

PDF

71.7 KB Created: 2021-09-18 01:18:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: c452a02385a229147141c41e29844440 SHA-1: 8f1f04585aeb2101533e2fe45942bf177349d9f4 SHA-256: e8788070680d95c463fad76f721ce96b61ab1c4a2daa908890c53f2ba226d32c
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with a high concentration of links pointing to distinct hosts, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, specifically identified as a phishing trojan. While no scripts were directly extracted, the PDF structure and embedded links are consistent with techniques used to redirect users to malicious sites for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.southforconstruction.com/frontend/web/ckfinder/userfiles/files/tujox.pdf In PDF document text
    • http://kdsonline.org/userfiles/file/deridus.pdfIn PDF document text
    • http://idroter.org/userfiles/files/94129128087.pdfIn PDF document text
    • https://organicfertilizerproduction.com/d/files/gozime.pdfIn PDF document text
    • https://mimpishiosatu.com/contents/files/24424453679.pdfIn PDF document text
    • https://phucatgarment.com.vn/ckfinder/userfiles/files/neduga.pdfIn PDF document text
    • http://metalltechnik-kutschi.at/19520269885.pdfIn PDF document text
    • http://wjcopy.com/upload/files/kafedinemuluvirerax.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16137e83ecbdb8---puriguruludakaronaxijonox.pdfIn PDF document text
    • http://beautifulmoda.com/userfiles/files/22572681089.pdfIn PDF document text
    • http://www.ruben.pl/ckfinder/userfiles/files/14434038704.pdfIn PDF document text
    • http://adas-muko.pl/photo/file/jinodaka.pdfIn PDF document text
    • http://guerrazzi.info/userfiles/files/78820774581.pdfIn PDF document text
    • http://iehyun.com/editorupload/file/vobiriroxijugijobunug.pdfIn PDF document text
    • http://tks-forever.com/upload/2021/09/11/file/rilobuxarifojiwi.pdfIn PDF document text
    • http://szintai.hu/ckfinder/userfiles/files/xoruxomewagesitagotalukev.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613b37c7ad6ef---56814791727.pdfIn PDF document text
    • http://www.workbythai.com/admin/assets/images/54664546342.pdfIn PDF document text
    • https://zlato-invest.cz/upload/files/xineravu.pdfIn PDF document text
    • http://cansuyu.org/resimler/files/90488094807.pdfIn PDF document text
    • http://top1np.com/ckfinder/userfiles/files/34938849127.pdfIn PDF document text
    • http://addon-colsman.somantec.net/ckfinder/userfiles/files/52548400410.pdfIn PDF document text
    • http://fruitsad.pl/images/file/68100915283.pdfIn PDF document text
    • https://esperanzadeavila.com/fotos/file/97791955188.pdfIn PDF document text
    • http://qapoll.com/2015/vat/upload/files/mubixuxilomomamera.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=crash+bandicoot+isoPDF 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_off0000b60b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB60B 16936 bytes
SHA-256: 94c491318b491245ed4f2060e43383bd5362b8190b6a757356900dd581d92f39
font_01_sfnt_off0000e17b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE17B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f992.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF992 10460 bytes
SHA-256: 794489d0fac3b001f4ae4301ba9efafc47df696affcf1b9f9eaf4bcbc7f2735c