Malicious PDF — malware analysis report

Static analysis result for SHA-256 de98e1e1648fe4a9…

MALICIOUS

PDF

73.8 KB Created: 2021-09-11 11:59:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 795ee5b698aa3d6fc5be122d994bf05a SHA-1: 2687a6d32419d1394a36d2c15b1485dd5e00b200 SHA-256: de98e1e1648fe4a9cb35b89f510329d9d21a782f9134ec3ef9af6f3e8d326a7b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external links, many hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to redirect users to malicious sites. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://synerhu.ru/uplcv?utm_term=mp4+to+wav+converter+free PDF link annotation
    • http://lignumweb.com/site/webroot/uploads/files/75425663871.pdfIn PDF document text
    • http://yongchengtech.com/uploads/files/202109071727068578.pdfIn PDF document text
    • https://baohohoanglong.com/userfiles/file/5679471122.pdfIn PDF document text
    • https://monamifrance.com/FileData/ckfinder/files/20210911_61638D3CB8645AA9.pdfIn PDF document text
    • https://aitalk.vn/upload/files/86364829466.pdfIn PDF document text
    • https://sssmri.com/ckfinder/userfiles/files/vuforasagawojunedi.pdfIn PDF document text
    • http://lsphc.com/userfiles/file///42864783085.pdfIn PDF document text
    • http://www.ags-sib.ru/ckfinder/userfiles/files/naselizadavelegifin.pdfIn PDF document text
    • https://vjlabor.pitscovn.com/uploads/Upload/files/pinedulabe.pdfIn PDF document text
    • http://www.smartusb.info/images/library/File/sajixovusog.pdfIn PDF document text
    • https://dazhonghua1688.com/ckfinder/userfiles/files/74335201951.pdfIn PDF document text
    • http://rockbond-aac.com/id-admin/fckImages/file/896655810.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613c3e4c4f64e---76880749506.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16130a394051e1---45949619794.pdfIn PDF document text
    • http://glovimex.com/uploads/ckfinder/files/26605185988.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/3b762b046e3f0d05972382f6f602fcfd/46810689844.pdfIn PDF document text
    • http://tizianaiberti.it/userfiles/files/kosujudux.pdfIn PDF document text
    • http://newkontakt.ru/userfiles/images/file/44990489960.pdfIn PDF document text
    • http://cheapneasytrafficschool.com/CheapNEasyTrafficSchool/pa/trainstation/uploads/image/file/bopuli.pdfIn PDF document text
    • https://forumsevens.com/images/file/26011412124.pdfIn PDF document text
    • http://ulsantour.com/FileData/ckfinder/files/20210911_26933BFA6786829D.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/161332d91518d9---78254880121.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_off0000be49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE49 10388 bytes
SHA-256: 81ee65868c04b548b1670978d29e3625c0aaf9d80bd6242971e45cb4cb449756
font_01_sfnt_off0000d60c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD60C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ee1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE1E 16992 bytes
SHA-256: 37af2be9b0be92e483a0df9198d13ba42d107e2471ce1e630ec0097dae9437f0