Malicious PDF — malware analysis report

Static analysis result for SHA-256 42e1de849ee9d718…

MALICIOUS

PDF

70.4 KB Created: 2021-09-17 07:47:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 71e565708b929f5b06f2bf9ef76d2c69 SHA-1: 6590274ccec74af0e5acfa27a7f7e7b42ce527dd SHA-256: 42e1de849ee9d71828f047d8fee141ec0d5e769cd2c831ba4c7284b14ab113ca
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document containing embedded JavaScript, which is a common technique for executing malicious code. The PDF also functions as a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting, suggesting an attempt to redirect users to phishing sites or download further malware. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://shastriratanchatterjee.com/ckfinder/userfiles/files/kanufe.pdf
    • http://agro-vostok.ru/userfiles/file/49885990938.pdf
    • https://www.thaiahpa.com/flash/files/futevawewumupogijuve.pdf
    • http://wxmx.cn/upload/ckimg/files/202109060704001341.pdf
    • https://kildevangen.dk/files/11025076722.pdf
    • http://lsbwg.com/ckfinder/userfiles/files/20210915/1614464653.pdf
    • http://hilimall.ae/uploads/files/biminaletopedexevoxize.pdf
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/1e3a74f4e7f0678d5711ca48a21f01c2/xitabalakafezekagokimadil.pdf
    • http://baiduvpn.com/upload/files/tujonibulimo.pdf
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/c1bb2d73950242ed7884d3528e571bf3/37614554110.pdf
    • http://hndgyl.com/v15/Upload/file/20219101834329602.pdf
    • http://winso.tw/userfiles/file/fumakufunoguna.pdf
    • https://thefencedocumentary.ca/adminfiles/file/28839241616.pdf
    • http://strap.sk/uploads/file/76186817032.pdf
    • http://nadafashionbelt.com/Uploads/file/55007250814.pdf
    • https://parvazyab.com/basefile/api203/files/72489320611.pdf
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613abf9a48a3f---14066491622.pdf
    • http://www.urbanwaterways.info/files/41757505940.pdf
    • https://zemtechnika.lt/public/site/0files/13451893058.pdf
    • http://tcsklife.com/filespath/files/20210910060820.pdf
    • http://kriosispl.com/cote_dor_import/admin/ckfinder/userfiles/files/kobegutuminoliji.pdf
    • http://kxxbs.com/uploadfiles/file/a/92783411106.pdf
    • http://portofmiamitunnel.com/system/js/back/ckfinder/userfiles/files/56708947879.pdf
    • https://mygoaltv.com/ipp/images/uploads/files/wapususugavapevezopuroken.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=electromagnetic+spectrum+frequency+and+wavelength
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b265.bin
22ea7baec9e1f6684daf9e4d4c88d5325982250fa805e00d5197208a70edf2f6
pdf-font-stream PDF embedded font (sfnt) at offset 0xB265 15164 bytes
font_01_sfnt_off0000d8f5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8F5 16792 bytes
font_02_sfnt_off0000f10c.bin
69686ec9d0299a96ebcaeeacc7a0bb336eeda2f7f9755d451fd4cec5b87e54eb
pdf-font-stream PDF embedded font (sfnt) at offset 0xF10C 11564 bytes