Malicious PDF — malware analysis report

Static analysis result for SHA-256 0885df6a6daab406…

MALICIOUS

PDF

77.0 KB Created: 2021-09-18 15:09:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1effbda7bafe57559eb1ed250d543cce SHA-1: 105d5ca282657befac7eca1679c3d5ae75321914 SHA-256: 0885df6a6daab4061a5954b96d1b244c41fc6d1247f07d0cf2e9963267df2746
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous external links, many of which point to compromised CMS upload directories, suggesting a phishing or malicious redirection scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious sites or download further malware. The presence of a link farm on disposable hosting further supports this malicious purpose.

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 http://hyosangjo.com/userfiles/file/20210903064818.pdf In PDF document text
    • http://caerulumpharma.com/upload/files/wirozorerogojurodusiba.pdfIn PDF document text
    • http://oa30us.com/userfiles/file/pubavetejufo.pdfIn PDF document text
    • http://clinivetmadonnadirosa.eu/userfiles/files/kelixunelirilizotu.pdfIn PDF document text
    • http://cayxaotamphan.net/userfiles/image/file/12080791197.pdfIn PDF document text
    • http://creatinglifeoptions.com/userfiles/files/ligoraxusitukakogurunara.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613300f890cb2---92408498310.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ea2e5e1882---wezixasowitawijenum.pdfIn PDF document text
    • https://unitytradefze.com/ckfinder/userfiles/files/nokijatawebumup.pdfIn PDF document text
    • http://biemmecommerciale.eu/userfiles/files/baletofugibafajif.pdfIn PDF document text
    • http://leruichem.com/upload/files/94506033838.pdfIn PDF document text
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613b9fb943904---rosigaxozebemodevotep.pdfIn PDF document text
    • http://htwy.com/upload/file/27363731636.pdfIn PDF document text
    • https://nirmalujjwal.com/public/ckfinder/userfiles/files/nabaledojegorekad.pdfIn PDF document text
    • http://zssadkowice.pl/pliki/94299102510.pdfIn PDF document text
    • https://www.hosotte.com/ckfinder/userfiles/files/zitoliludejonixat.pdfIn PDF document text
    • http://savoie-outils-coupants.com/ckfinder/userfiles/files/xejikufus.pdfIn PDF document text
    • http://www.tokyomagic.jp/images/library/File/6311520613.pdfIn PDF document text
    • https://ms01bet.com/contents/files/61424275713.pdfIn PDF document text
    • http://synergytaekwondo.com/click2buy_newp/userfiles/file/regudoko.pdfIn PDF document text
    • https://ukmalayalamnews.com/userfiles/file/89700551203.pdfIn PDF document text
    • https://auditorescr.com/ckfinder/userfiles/files/31697152720.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=wcc3+60+mb+apkPDF 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_off0000c2e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2E8 20240 bytes
SHA-256: 510fe29d4459323fe565f2303ef136bb29cd383b065b5a1c0e13c09eb69bb99c
font_01_sfnt_off0000f7d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010feb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FEB 10364 bytes
SHA-256: 056ac571e7e84bbc672bbef83b616449acc51f1b51f3284274aa2b987116a2af