Malicious PDF — malware analysis report

Static analysis result for SHA-256 090d04f95622eff4…

MALICIOUS

PDF

73.9 KB Created: 2021-05-12 22:38:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 6469930446e41f83222f65100d0ab758 SHA-1: 4241c4f98f14633c5069532664b23041cd29aea0 SHA-256: 090d04f95622eff40fabf90d25750fb73ad28e6b715f4593a92f3709374f34f2
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised WordPress sites, indicating a link farm designed to redirect users to potentially malicious content. The document body is heavily obfuscated and contains metadata suggesting it was generated by wkhtmltopdf, but no clear instructions or lures are discernible from the readable text.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608019335f0a1---rofigoxiz.pdf In PDF document text
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bc873d03f1---56537136524.pdfIn PDF document text
    • https://www.movingwithmagna.com/wp-content/plugins/super-forms/uploads/php/files/3b9d5614cd0384d63a7170d3cf2d7b77/58120861056.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608fc3d9abe1a---14142732927.pdfIn PDF document text
    • https://realestateconnect.biz/wp-content/plugins/super-forms/uploads/php/files/taq122j1elt1rbrmu7ft4obf64/tiwiz.pdfIn PDF document text
    • https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/dd93bfbbd65d3b836eb2966d85d22e70/duzovitolimonopun.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160910d8eeaf1b---86804772711.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/qd5ipq9c8ucuggap9nsncv21f7/beseko.pdfIn PDF document text
    • http://alpanelektrik.com/depo/sayfaresim/file/6565276076.pdfIn PDF document text
    • https://www.citysecurity.org.uk/wp-content/plugins/super-forms/uploads/php/files/jkn9l5o45deuruo8ksgh71r02q/jirunokumawilixijedux.pdfIn PDF document text
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082c444bf38a---vikaxumijufeturuv.pdfIn PDF document text
    • http://bioident.pl/photos_fck/file/93385422125.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607856d8c496c---womizorowarotivivoz.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/kaveke.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/3159bcf1ac8bea23c72746c23b376126/72074561846.pdfIn PDF document text
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/u9r8v804e7fnmg6ttf66cprgn0/50103729264.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=bootstrap+studio++linkPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d802.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD802 4828 bytes
SHA-256: 9244a11c8d10492e8561ad19e2d1832bc5a6f2efc88963e2c675ff0185205fea
font_01_sfnt_off0000e86d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE86D 10548 bytes
SHA-256: 5e1b9ef97ca1e8c04a9e316511a459dbca18fd12b0d4b213c19d986f16ac05cb
font_02_sfnt_off00010ca3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CA3 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3