Malicious PDF — malware analysis report

Static analysis result for SHA-256 258a1a924fb0806f…

MALICIOUS

PDF

90.3 KB Created: 2021-08-14 00:00:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c6243e894da1e2787e47660b81c2f163 SHA-1: f8420b8528e63070b788319a454302013912e7e4 SHA-256: 258a1a924fb0806f09fb6534248232da4adecb92a162391b765f209d799d0dcf
196 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites and disposable domains, suggesting a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly indicate malicious intent, likely to redirect users to download unwanted software or further malicious content. No scripts were extracted, but the link farm itself is the primary attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://catamma.ru/uplcv?utm_term=smashy+road+2+mod+apk+unlocked
    • https://childrencareandliteracysociety.org/userfiles/files/52364733494.pdf
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/26023116604.pdf
    • http://hglobaltour.com/FileData/ckfinder/files/20210701_BD0D7AC07477DBB3.pdf
    • http://cartonwrappingmachine.com/userfiles/file/norikobuvoti.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/61167ccdb52c94ac5dffdaf43d6deb0a/samuluwufaxesadefov.pdf
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160983b375604e---22407053292.pdf
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1607204779da37---jukemer.pdf
    • https://catbasailing.com/upload/fck/file/fozewakebavosikix.pdf
    • https://nguoixunghekiev.vn/userfiles/file/nejudoragubujisejogukov.pdf
    • http://slhs1958.com/clients/18590/File/63691351552.pdf
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160c8e1ff107af---86774631189.pdf
    • http://autothudo.vn/upload/fck/file/ramopomobutidep.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c411db5492.pdf
    • http://krajinar.cz/soubory/files/xobex.pdf
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/6n8v4php97717dhrpns89muu34/21468216394.pdf
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a02d4f5dbf2---56244034440.pdf
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/v4c4lmorskfpfvmqlsp40r3nht/lufolotiwipokanukobabala.pdf
    • http://menafundinfo.com/userfiles/file/biput.pdf
    • http://hindel-relax.ch/ckfinder/userfiles/files/wetaradegalivoropepaf.pdf
    • http://asupuro.com/user_data/image//file/setesesiworesu.pdf
    • http://barsugo.com/ckfinder/userfiles/files/26505790279.pdf
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6c0f3581f6---tejazidat.pdf
    • https://retta-bg.com/userfiles/67022861891.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_off0000fbdb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFBDB 16792 bytes
font_01_sfnt_off000113f2.bin
66dd789837853f3ab504309161df9b305f2b1fb946a4de8b425784745de5b3b5
pdf-font-stream PDF embedded font (sfnt) at offset 0x113F2 11088 bytes
font_02_sfnt_off00012da7.bin
df512c19b44f03cf51ceff0b320a5df1655062684ac1c15bfcc76c3cde4225fb
pdf-font-stream PDF embedded font (sfnt) at offset 0x12DA7 17020 bytes