Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab50f6fbce0a5405…

MALICIOUS

PDF

85.7 KB Created: 2021-09-01 17:21:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: cb8df1f76831f7d51f4e1bac360945e3 SHA-1: 6cc7f5f4618827a9a76259d752f768cbb755ad55 SHA-256: ab50f6fbce0a540550f05a660c34ddaf385321157338ae48d1939f702ea1a8d1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, a common technique for executing malicious code within PDFs. It also features a link farm pointing to multiple compromised websites and disposable hosting, suggesting an attempt to obscure the ultimate destination and evade detection. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://inwebjor.ru/uplcv?utm_term=who+was+to+blame+for+romeo+and+juliet%27s+death PDF link annotation
    • https://aannemingsbedrijfbarthulsbosch.nl/userfiles/file/53026765974.pdfIn PDF document text
    • http://www.magicapro.it/wp-content/plugins/formcraft/file-upload/server/content/files/16121a6f450916---fanikezilafa.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-7-21/20210721191445492831.pdfIn PDF document text
    • https://praward.tw/wp-content/plugins/super-forms/uploads/php/files/eec150ab4a812f598de51f87743e1cfb/65332718904.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/b410bca78ce18e449daee264e265d297/jibewenadutavozoroma.pdfIn PDF document text
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/482c8c382f22fca393915e6916d17751/15228609268.pdfIn PDF document text
    • http://speakingaboutnetworking.com/ckfinder/userfiles/files/gaxodabowe.pdfIn PDF document text
    • https://aadharshilaschool.org/userfiles/file/zejipesuvopuzavano.pdfIn PDF document text
    • http://leasingtowers.com/ckfinder/userfiles/files/21983923676.pdfIn PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/cjha9p2hhg2p01osev8fcfq1j1/xowubajumevaxupifupozas.pdfIn PDF document text
    • http://maybomchuachay24h.com/Images_upload/files/9633699036.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/ziwojegiliz.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/dd201cf8a686327f38aa859e73bd1cd3/rawenefusi.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607aac8616cd8---39918385964.pdfIn PDF document text
    • https://imad0c0.com/js/ckfinder/userfiles/files/86087097592.pdfIn PDF document text
    • http://adaviestransportltd.com/userfiles/file/kigemivilutubolunugezoko.pdfIn PDF document text
    • https://oriental-kitchens.com/userfiles/files/36575073915.pdfIn PDF document text
    • https://thietbixanh.net/uploads/files/36610996504.pdfIn PDF document text
    • https://ascinfratech.com/clientprojects/trading/file/12371810148.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/xozivivesefelebeza.pdfIn PDF document text
    • https://peltonfell.org.uk/ckfinder/userfiles/files/patugogifef.pdfIn PDF document text
    • http://guss-ex.de/uploads/fck/file/97898590878.pdfIn PDF document text
    • http://ypperfect.com/ckfinder/userfiles/files/wilifebimukufil.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_off0000e9cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9CD 11100 bytes
SHA-256: b7f5d1d5916ba58b3a7852b765aa8798626b196438fe1a035c9fedc667d75e2a
font_01_sfnt_off00010385.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10385 17248 bytes
SHA-256: 6245d115be203a10a89b755d364074a9772525f8518c26f77a49062d85c31f58
font_02_sfnt_off00013077.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13077 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1