Malicious PDF — malware analysis report

Static analysis result for SHA-256 aef0c60dffa20719…

MALICIOUS

PDF

87.3 KB Created: 2021-06-26 00:15:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cafa4b72a5e1b4202985a21f0a30070e SHA-1: 4a90d0f86e7a674cab7f4128fcdf779c0c24583a SHA-256: aef0c60dffa207192131bc88d8e689899025be45767faf0719c538ea9a37f6a7
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs that point to compromised WordPress sites, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment that it is part of a phishing or malware distribution scheme. No scripts were extracted, and the document body was unreadable, so the primary indicators are the numerous external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • 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://archism.ru/uplcv?utm_term=ff7r+buster+sword
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160cd5be0e262e---zojugi.pdf
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/279f0b30caa30f0ce8dd397b10c6b75d/toxotawasikujazuripa.pdf
    • https://seeandhearbetter.ie/img/shop//contents/72723722218.pdf
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/8db1f03dceabaaacf7248980ac227ff8/vutokixaxepovev.pdf
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/i9fj4neogbf2e035t0e99snidc/jusudu.pdf
    • http://helpibr.org/clients/f/fe/feaff840d005acecac0f151e8679c8db/File/vanurolivesewi.pdf
    • http://anhuifan.com/upload_fck/file/2021-5-20/20210520074238609642.pdf
    • http://nfraccon.org/userfiles/file/35764212447.pdf
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbc828a74b---81997074690.pdf
    • https://www.profiemg.cz/upload/ck/files/89142466698.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bcc42bee0e5---14493513475.pdf
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607d7b9c1f8d9---49408452264.pdf
    • http://4grd.com/cmsimages/file/metopesulakimaduf.pdf
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/6666a8b55a5e599a770dc1b89fab05f1/78801660419.pdf
    • http://oreade-breche.fr/userfiles/file/76677648294.pdf
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/a6557ca0f4c45dcae87daf2c121d7f35/vilovafukagomusogepurav.pdf
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16077385379cf3---tutaluxibilokegetewidut.pdf
    • http://www.urbanwaterways.info/files/nubefuwaxezel.pdf
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c0fea60ad5d---54775427590.pdf
    • http://mattstergamer.com/wp-content/plugins/super-forms/uploads/php/files/2ie6q9ah1gucojpikfhdkh47pr/fusaretunowevebopizol.pdf
    • http://simkoongschool.com/uploads/editer/files/28802040.pdf
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160741359a1258---lepivufixemamukege.pdf
    • http://adamlegal.com/userfiles/file/juzozif.pdf
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c45c810fea---40357669589.pdf
    • 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_off0000f1ce.bin
45e65fec991d623febec21003b828ddfe60cc7e407a5d675df592b868ac17187
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1CE 17132 bytes
font_01_sfnt_off00011ef8.bin
92f2aca4c7670fb9caace36c48cad1985e83e69dc0b56fab5890b8a89d5c289a
pdf-font-stream PDF embedded font (sfnt) at offset 0x11EF8 10296 bytes
font_02_sfnt_off00013668.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13668 16792 bytes