Malicious PDF — malware analysis report

Static analysis result for SHA-256 645fc881915890c4…

MALICIOUS

PDF

83.0 KB Created: 2021-06-28 21:00:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5190f93bf48cf61a5437ce0fc8f5ad0f SHA-1: 7e98759f19b6eff992b80102f271dac10573bce3 SHA-256: 645fc881915890c44cf53933609c94a6016e1d124d8bfd2c00ed9d5f7e50dceb
156 Risk Score

Malware Insights

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

The PDF document contains numerous embedded URLs, many of which point to compromised WordPress sites utilizing formcraft or super-forms plugins. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document's structure as a link farm suggests an attempt to lure users to external, potentially malicious, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 6

  • 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.
  • 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://huntic.ru/uplcv?utm_term=continuous+professional+education
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/160a7ecb85bc54---warozuminosoruxemel.pdf
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a7f8925257b---gofovogogatoxemutoline.pdf
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608b36f88fd0b---73619503898.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bc4f3163001---72293241317.pdf
    • https://quickonboarding.com/wp-content/plugins/super-forms/uploads/php/files/6059ec698607e8651f6cdf9b1b3af83e/66090817949.pdf
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b360e824a3b---jumozogimuno.pdf
    • https://x-software.cz/data/file/moguguvo.pdf
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/160a2b91d12df6---wuzelusa.pdf
    • https://etonbio.com/newsLetters/images/file/bofuwononave.pdf
    • https://xn--80aaaglcftt5alesfkk7f.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/e879e0b404e8e303d558f6bce9d12981/sozesizuxaxisataxupudifiz.pdf
    • http://irinaburmistrova.ru/files/42244781965.pdf
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/160aafa0949126---lupirogunafogam.pdf
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/98gsp1fbllfkvp2b76hv9rtb8i/jilakolavufutodokufazo.pdf
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/fa3bari7lr4m1o89odhc8bak6e/zenuno.pdf
    • http://leaguengn.com/userfiles/file///kuxojoxivoribepiwa.pdf
    • http://sbsinternationalschool.org/sbsisnew/userfiles/file/lusezitugoxeval.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080460487a0a---fesilogawenaloxe.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd555e7460d---tukobanodo.pdf
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/286be98df33bd317a972f423453710da/92075665249.pdf
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e7d429532e---fojukufebi.pdf
    • http://lapenya.cat/imgjovesnaves/file/29483376529.pdf
    • http://bioterapiazabiegi.pl/obrazy/file/79776062650.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_off0000e4b0.bin
42233167c1b641b75a876f5c9c2dc8604d1137b003572734d74bb328ade4e282
pdf-font-stream PDF embedded font (sfnt) at offset 0xE4B0 10744 bytes
font_01_sfnt_off0000fd8a.bin
82a6dd9bac5f2ee10c30cf9f215d4dbff2766a235559a9db9a4fa278aeed5b40
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD8A 15964 bytes
font_02_sfnt_off0001267e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1267E 16792 bytes