Malicious PDF — malware analysis report

Static analysis result for SHA-256 b05dc440e78411d1…

MALICIOUS

PDF

72.5 KB Created: 2021-07-01 23:35:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 82710121501f2b1708065c3c4d968f89 SHA-1: 9e7b30cc23466b4888a5582d3f7e01bc25d8160b SHA-256: b05dc440e78411d16c37e589bea87d84946dd41e690b259a44eee8b3407450e6
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to numerous URLs hosted on compromised WordPress sites and disposable domains. These links likely serve as lures for phishing attacks or to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://philabc.ru/uplcv?utm_term=decor+and+more
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607c41c025d10---nuwakuloket.pdf
    • https://contabil-fiscal.ro/mm/file/topomupidivokedune.pdf
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1606f55ebe049d---28385841754.pdf
    • https://qualitylightsolutions.com/wp-content/plugins/super-forms/uploads/php/files/079b211e9fecb9b8bd9b4872505e1e1b/xiwopu.pdf
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/16080f5a73bf85---7168955602.pdf
    • http://popnmusic.fr/userfiles/file/futaf.pdf
    • http://lab4050.com/upload/editor/file/jebesonojijazefa.pdf
    • http://ikhmongol.mn/ckfinder/userfiles/files/22538276629.pdf
    • http://gulfcoolcontracting.com/uploads/userfiles/file/file/34314936282.pdf
    • http://goteneplast.se/files/images/file/21466814070.pdf
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/6e94c57a8cb23560ca79df3f95afa7b5/xabufuredapofipuf.pdf
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/fq2alprbeh2oltijtqv7s75f2n/162789376.pdf
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609e2fada5d92---mibaludalakomomuja.pdf
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2b8e7d974a---18751295275.pdf
    • https://thediamangroup.com/_images/files/nubewujomaki.pdf
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ad776570c15---ridivi.pdf
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097669bcaf77---49087915722.pdf
    • http://afghansolar.com/userfiles/file/nawunamenonavafotul.pdf
    • https://ambientltg.com/wp-content/plugins/super-forms/uploads/php/files/367cc57e0d09bb7a2d1086b467a6ac13/78537391913.pdf
    • http://gymostrov.org/gymostrov/userfiles/file/risamorimiper.pdf
    • https://www.vedaaz.com/wp-content/plugins/super-forms/uploads/php/files/a0eec41c3262e76965c4254823e5ad13/41540338412.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_off0000b894.bin
a4b89d6e09b42ba5141c3cc4913967a57e8b274c0b06dd20b56ea8a2a7407aae
pdf-font-stream PDF embedded font (sfnt) at offset 0xB894 17116 bytes
font_01_sfnt_off0000e526.bin
5f58b0309b6eb8adaf96b0f26d7020334da55b1127eedb598b0e82fa6523014f
pdf-font-stream PDF embedded font (sfnt) at offset 0xE526 10128 bytes
font_02_sfnt_off0000fbac.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFBAC 16792 bytes