Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a97988f3ce9d46d…

MALICIOUS

PDF

73.3 KB Created: 2021-07-07 21:20:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3531f0221782b7cbe5d556a9672a6764 SHA-1: 8723d59b73c29bae7363b64e53cf7a0b0357abf6 SHA-256: 4a97988f3ce9d46d7fcb5b50b7571544f0b5bf6547b3e799cfbcc05056bd3b5f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.012 Process Injection T1204.002 Malicious Link

The PDF contains a link farm pointing to numerous URLs, many of which are hosted on compromised WordPress sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094ab4c16180---8679402107.pdf
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/3e5bfa57f1ab8ee07c7daf16b7adfb41/rijoz.pdf
    • https://pmms-online.com/assets/file/91061651938.pdf
    • http://lab4050.com/upload/editor/file/tokod.pdf
    • http://rjbmachinery.com/d/files/57709685113.pdf
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/0fd07911619e64e42a96953a18dd4d14/30778149601.pdf
    • http://divapharma.com/uploaded/file/71326530346.pdf
    • http://zonweringbelgie.nl/ckfinder/userfiles/files/62361372039.pdf
    • https://fruzsiflame.hu/userfiles/file/pegon.pdf
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160965e6131fda---22612527148.pdf
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/d37b52cf59541147f1410e7e64f44bec/93991474606.pdf
    • https://bestofbucerias.com/upload/file/65936649289.pdf
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1608b29ad14540---90669122492.pdf
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e16cb9aad17---juzavo.pdf
    • http://stainless-faucet.com/uploads/htmlupload/files/7703533771.pdf
    • http://creativeindustries.ru/uploads/userfiles/file/24632379919.pdf
    • https://grupo-bahia-real-estate.com/ckfinder/userfiles/files/77847363240.pdf
    • https://vestol.bg/files/file/xumukixanimisujaloradura.pdf
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc5c002de4---63559039352.pdf
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c733d20922b---55853862476.pdf
    • http://elitaliaweb.it/upload/file/70859901186.pdf
    • https://synersys.fr/contenu/file/3751004223.pdf
    • http://cancercareresearch.com/userfiles/file/geririki.pdf
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9c8505e79---32557180741.pdf
    • http://angarakshaksecurity.com/userfiles/file/853783381.pdf
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/a6tg2vdn0t8uf40jbrefd1qd7s/robezib.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=us+history+eoc+review+guide+answers
    • 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_off0000bdc9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBDC9 16792 bytes
font_01_sfnt_off0000d5db.bin
4eb8a1109c73ac2214e02c43dfa31745f72adb685bcfb1265a26aa02fd9d336d
pdf-font-stream PDF embedded font (sfnt) at offset 0xD5DB 15820 bytes
font_02_sfnt_off0000fe33.bin
283a4940218d86100fd7e1f5fd8de1910641ae48b82a30ef8cfd293f510bfc1f
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE33 10976 bytes