Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a958167b62d96aa…

MALICIOUS

PDF

97.4 KB Created: 2021-07-05 13:11:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6da14c9c58bb0b18005da163a627fcd0 SHA-1: 521d2b0a14a44ab5143a7cdb1f409eb82a00716b SHA-256: 4a958167b62d96aa857280a5349a4e19a6e8f75f767eab1bc6db88a6c5293a21
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress upload directories and other disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lure users to malicious sites for further exploitation or phishing. No scripts were extracted, and the document body was unreadable, but the URL structure and heuristic firings are sufficient to assess its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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 http://statsale.com/data/upload/ck/files/54834660904.pdf
    • http://hi-reid-solutions.com/wp-content/plugins/super-forms/uploads/php/files/6f7e3180ab6ea1199f12413f6792823b/18552725569.pdf
    • https://sheenabusesandcoaches.com/userfiles/file/57632657855.pdf
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/v9ppo6r48l6qleb57e2g6je2ev/36801151457.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/t19c0j9aujmrk49u5jmu61lob2/95263587983.pdf
    • http://aweibel.com/Photo/file/15395081966.pdf
    • https://argumentua.com/i/file/malaxijotafilufew.pdf
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/04ab50a30aa8ecc227b122ec6d2fe5c2/25711485471.pdf
    • http://bjallstar.com/upload/file/mixediruweroxuwujewotibi.pdf
    • https://www.freshstartdigitalmarketing.com/wp-content/plugins/super-forms/uploads/php/files/2cdb4f24fa037508c90d8bd3ab13c11c/rikiv.pdf
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608927a14f588---libomazamumulow.pdf
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afd29911160---19751679542.pdf
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a39017e31a7---gonomikezavodiwiwuzis.pdf
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/772805uttqd8qq6j1leovkatlh/lazanusirinorawalofarizi.pdf
    • http://longarmquiltacademy.net/fckeditor/userfiles/file/rufobo.pdf
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/72a866ce04779cc62bb6c87f0ef01d01/vogexajapizenezigiwumuv.pdf
    • http://ac-kenigsberg.ru/files/file/17044096047.pdf
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/3gqf5etn2gsp081r4gemfq08c1/29686131909.pdf
    • http://pivotal-technologies.com/userfiles/file/40403084151.pdf
    • http://4grd.com/cmsimages/file/dapukurodatopaw.pdf
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b67bbeb1cb---bumekari.pdf
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cf9d8ed980---39301674252.pdf
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1606cdfd5d81a4---migilet.pdf
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/61ca52ddc15fcb6e02f37c2ebb10e385/jijimewopinanalataled.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=for+honor+tiandi+armor
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fd6f.bin
658fa8a932abe9a8e2fd3097a338df2c4c6a57527ccb3d2531293bf350736099
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD6F 7828 bytes
font_01_sfnt_off000117eb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x117EB 16792 bytes
font_02_sfnt_off00012ffd.bin
eb146339e342b3bf712a36d09601f94c6c8c4b261b0f0709843975a9b5ac160e
pdf-font-stream PDF embedded font (sfnt) at offset 0x12FFD 19712 bytes
font_03_sfnt_off000161b9.bin
77401cf7a58f0140f5ebd8b9702d93c56862ab8958a8b608d48777fe06a0ae12
pdf-font-stream PDF embedded font (sfnt) at offset 0x161B9 10144 bytes