Malicious PDF — malware analysis report

Static analysis result for SHA-256 71a0c1548332b7c7…

MALICIOUS

PDF

97.0 KB Created: 2021-07-30 20:29:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1a892773560d43a1eb1d8f24f5699157 SHA-1: cb2ebd2ad28da77ece34c79eecbd1032aab2c374 SHA-256: 71a0c1548332b7c77d7470501b6472079ca40a1837b75d4a970a0de29108ccd6
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing users to multiple URLs, many hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to phish or redirect users to malicious content. The document body is heavily obfuscated and does not provide direct clues to its purpose beyond its structure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://huijingweb.com/upload_fck/file/2021-7-19/20210719182723440820.pdf
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/97ad95e1495ab8ef94581ba6badec9fa/48484214076.pdf
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb603c23fb---bigux.pdf
    • http://championsview.net/userimages/77073947769.pdf
    • http://utuin.net/files/fckeditor/file/xabilutujimir.pdf
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160766c4c54e26---fidomurikunividepudeniw.pdf
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/4c9fefe77bb5a9009b2bc9c904986ae6/60005741203.pdf
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/160bd60dc41160---16402314152.pdf
    • http://bagiez.com/userfiles/file/jumazajanitosam.pdf
    • http://xn--e1aaafipco3bk8gra3b.xn--p1ai/upload_picture/file/2514003193.pdf
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/16094a984c367d---niwomajabigugegeluvimu.pdf
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160b0dba3a8ec9---69854053407.pdf
    • http://decamiones.com/userfiles/file/lukiz.pdf
    • http://nappsa.org/userfiles/file/mosazis.pdf
    • https://egokituz.eus/files/galeria/files/vibuvitetijivuverikok.pdf
    • http://www.asejnrtigers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609be810c6561---53595019277.pdf
    • https://www.cpro.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16076215443afb---48561504189.pdf
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ecf0848c05---wosalujasagijafaboxidad.pdf
    • https://ncvpte.in/userfiles/file/loxigo.pdf
    • http://perlawarmii.pl/userfiles/file/29400097204.pdf
    • http://tragiaocolamsapa.com/userfiles/image/file/xepedofepijudetudewu.pdf
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/d37v3cnh4db6u3ucgs1d3l1j2e/42639998392.pdf
    • http://www.ekoforte.com/upload/file/satoma.pdf
    • http://kapelski.pl/userfiles/file/88404742665.pdf
    • http://emanuelmlevin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/32820421831.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=broadcom+802.11+b+g+wlan+driver+vista+hp
    • 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_off0001155f.bin
8730a901ae56146d048d4c35ad993f20c18a56567cccf2431479b0737eacccfe
pdf-font-stream PDF embedded font (sfnt) at offset 0x1155F 16744 bytes
font_01_sfnt_off00014144.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14144 16792 bytes
font_02_sfnt_off0001595b.bin
bbdf23be3feac1d7323bdb3f0466c1d82530ae673f615d9b0826a7124af0c4f8
pdf-font-stream PDF embedded font (sfnt) at offset 0x1595B 11876 bytes