Malicious PDF — malware analysis report

Static analysis result for SHA-256 d87c00b2c08caba0…

MALICIOUS

PDF

82.6 KB Created: 2021-09-24 05:22:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b85a457c64a076c6f7edea6e7ae4e0a6 SHA-1: 744651afa4835806982f913cd06afc6c6db3b97b SHA-256: d87c00b2c08caba0b42eb23599e5346f386e65fdc59583241aeedd963e0a1921
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, forming a link farm. This suggests the document's primary purpose is to redirect users to malicious sites, likely for phishing or to download further malware. The ML classifier strongly supports the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • 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://wastran.ru/uplcv?utm_term=android+telefona+imei+atma+kodu PDF link annotation
    • http://7seapharmtech.com/Uploadfiles/files/6823109191.pdfIn PDF document text
    • http://formel1vermietung.de/userfiles/file/11231715093.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613f77057080d---78795478618.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/ke19ot9lvf7lmi1m92p0gv0ud4/vigebasudujipu.pdfIn PDF document text
    • http://www.performhabitat.fr/bundles/astadmin/js/ckfinder/userfiles/files/verogofidixomoxenosidage.pdfIn PDF document text
    • http://fra2ange.it/userfiles/files/lokavilikuwekebiriro.pdfIn PDF document text
    • http://huichem.com/ckfinder/userfiles/files/100437021.pdfIn PDF document text
    • https://matharu.ae/userfiles/file/297146323.pdfIn PDF document text
    • http://ovartec.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fc4378ffee---12706676371.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145769830767---kegubude.pdfIn PDF document text
    • http://koovappadyscb.com/ckfinder/userfiles/files/posenivanuju.pdfIn PDF document text
    • https://incoyun.com/calisma2/files/uploads/47256005775.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/e1bs2ek6ol7b9g73ieb1vh6d7g/4324496519.pdfIn PDF document text
    • http://gbfrjournal.org/pds/userfiles/files/10525025139.pdfIn PDF document text
    • https://drhuanghair.com/uploads/files/202109230936268606.pdfIn PDF document text
    • http://lifebeachvilla.com/uploads/image/files/79273024467.pdfIn PDF document text
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/1fd1a646f99ab303730c131a531a1243/raziv.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/74813301558.pdfIn PDF document text
    • http://needychild.org/ckfinder/userfiles/files/24849381162.pdfIn PDF document text
    • https://network-italia.com/file/momexoxusadivo.pdfIn PDF document text
    • https://thepainter.asia/upload/files/gosukumefexavetejitopa.pdfIn PDF document text
    • https://gyn-koe70.de/obrazky/file/fonujazalesugojelarapop.pdfIn PDF document text
    • https://associazionebriciole.it/public/file/sugokobuz.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_off0000dcc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCC4 18764 bytes
SHA-256: b4a8bdd483c4d248d059fbb1966b34d4e2a846620eab6592c5078655fbc4c916
font_01_sfnt_off00010b4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B4D 10520 bytes
SHA-256: 1130c1640b511ed589113bc78c7141a5cda63571d41e9ae5dccf72ea4358e8dd
font_02_sfnt_off0001233a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1233A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1