Malicious PDF — malware analysis report

Static analysis result for SHA-256 cfbc40b61883819c…

MALICIOUS

PDF

90.8 KB Created: 2021-07-23 04:00:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: cc73eeef02ea6f6909b965c13b82dfac SHA-1: a9dd1ca85368dddfa4ede60d3458529364794020 SHA-256: cfbc40b61883819c2dcea6263ba1b74a995f8f21fd2f3b62247c2ca85674e577
156 Risk Score

Malware Insights

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

The PDF file contains numerous links pointing to compromised and disposable domains, indicating a phishing or malicious redirection scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lure users to external sites for further exploitation. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL analysis and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://npxbyy.com/wang3_3_10_27/Upload/Upload/file/20217151421434777.pdf In PDF document text
    • https://burmesecatclub.nz/wp-content/plugins/super-forms/uploads/php/files/4f24bba655d06d611946550b35916a0a/65098512585.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/juvojakusi.pdfIn PDF document text
    • http://wooshin.kr/uploaded/file/116246553760e0c2b101980.pdfIn PDF document text
    • https://envomask.com/wp-content/plugins/super-forms/uploads/php/files/6fef3884c9fa04cdcac9aa8acef45a22/92459013307.pdfIn PDF document text
    • https://rajatotogroup1.com/contents//files/midawokizowogalome.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160aa3c828f340---jesonebamipobena.pdfIn PDF document text
    • http://anhuizhkj.com/upload_fck/file/2021-4-30/20210430143226649153.pdfIn PDF document text
    • https://truck-diagnostic.ru/wp-content/plugins/super-forms/uploads/php/files/3c785712bc87ba86bd930247105f2137/65721057564.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a156b4b08f2---daxawifetimosoraval.pdfIn PDF document text
    • http://hzjksj.com/images/upload/File/mobodoj.pdfIn PDF document text
    • http://firegallery.ru/img/upload/naguzasejawelitanileja.pdfIn PDF document text
    • http://aven.su/userfiles/file/tapiterefepajodesijuziki.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072949301de0---xododute.pdfIn PDF document text
    • https://soechi.net/userfiles/file/rubonijobefet.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/39645784105.pdfIn PDF document text
    • http://associacaoguainumbi.org.br/wp/wp-content/plugins/formcraft/file-upload/server/content/files/160720b270c42f---8282116416.pdfIn PDF document text
    • https://dodatnagarancija.com/userfiles/file/6218558135.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e7f18596e7f---59169062985.pdfIn PDF document text
    • http://adance0112.com/upfile/editor/file/dafifegasugem.pdfIn PDF document text
    • https://mama-light.net/business_school/uploads/file/4091400764.pdfIn PDF document text
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/u16j93jcretv6ak20hle9bolq2/xalikojikirarutalutoniju.pdfIn PDF document text
    • https://juegosinflablesarizona.com/files/99549774337.pdfIn PDF document text
    • http://gardnersunited.com/clients/e/eb/eb3320446930dd457027df34457c622b/File/kigusenilixawuvedapapula.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=law+of+motion+of+newtonPDF 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_off00010179.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10179 16884 bytes
SHA-256: 8f6cf061b1dd7ae7f15815a3c699260f5f4b5ddf910532b8240ede32c63803de
font_01_sfnt_off00012d94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D94 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000145ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x145AB 10104 bytes
SHA-256: 77021daaabcad0b586ba1e1bfe1d5f9d08016c72905ea8a2e3fd23627b872130