Malicious PDF — malware analysis report

Static analysis result for SHA-256 57c6a48d4c92a9ca…

MALICIOUS

PDF

69.1 KB Created: 2021-09-24 14:27:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f5c238fe41df07fbb3f6814533d1319a SHA-1: b668aa32f8f825a73b9304d3aaff6006cb1c7c76 SHA-256: 57c6a48d4c92a9ca53098ac57ed19569278fd15d7f3aa45f80d6fb70960dcc0c
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many embedded URLs pointing to potentially compromised websites. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure suggests it's designed to redirect users to external, potentially malicious, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614232891c126---36203492207.pdf
    • http://centroolosprato.it/userfiles/files/batixopifabesafip.pdf
    • https://alquimia.in/admin/fckeditor/editorfile/makugisiz.pdf
    • https://gogift-it.com/userfiles/files/pukipoxokerebuwis.pdf
    • http://jingluo.net/uploadfiles/files/75468117627.pdf
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613032e40654e---11319150969.pdf
    • http://ijiantu.com/filespath/files/20210921144900.pdf
    • https://ntct.dz/ckfinder/userfiles/files/zeruvafufexonir.pdf
    • http://imosa.asia/uploads/files/202109071255253139.pdf
    • http://urparitet.ru/admin/ckfinder/userfiles/files/fukadipuxetunimem.pdf
    • https://12tiga.com/contents/files/mozosemotujofozowajanu.pdf
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/loj6pqu4mq848lahm3aaosliq2/vumifazos.pdf
    • http://kapalishakti.com/ckfinder/userfiles/files/tekujugaremisumebi.pdf
    • http://baheth24aqari.com/ckfinder/userfiles/files/wabamagijaxikijoluxogado.pdf
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614a2f85c2f4b---14246654609.pdf
    • http://backkwang.com/userData/board/file/91671641265.pdf
    • http://daisytalavera.com/userfiles/files/52539246920.pdf
    • http://sunriverps.com/data/editor/file/74196646560.pdf
    • http://larben.cz/media/images/upload/file/monajife.pdf
    • https://soudureornementalelauziere.com/upload/editor/file/zilomixev.pdf
    • https://equinox-e.com/upload/UserFiles/file/gagelatu.pdf
    • http://theexplorerthai.com/userfiles/files/25329499518.pdf
    • https://redac.ch/upload/guxikose.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=top+launchers+2021
    • https://mediaget.com/userfiles/files/gubomijexuxotasan.pdf
    • 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_off0000aee6.bin
921029b27a7282c16f5bb42d5b1dfce8ff454d6b739b8d69178e2176e1aa7941
pdf-font-stream PDF embedded font (sfnt) at offset 0xAEE6 10636 bytes
font_01_sfnt_off0000c745.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC745 16792 bytes
font_02_sfnt_off0000df57.bin
f899f89853898e452d0d94cac3ebafc32ad7fd612ef9c1a08a09587ae0333df8
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF57 15756 bytes