Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a530b406b8879ad…

MALICIOUS

PDF

81.2 KB Created: 2021-09-18 05:17:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 55c3449f5a12ef5b1c8ce271f9c33cae SHA-1: 40d8baf6c81909b3cf08d4ff043961afa16013cd SHA-256: 4a530b406b8879ad6557b0777a651e146dfe127828ed777f5e0da93f4c882e8f
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to disposable hosting or compromised CMS uploads, indicative of a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple external URIs and link farm heuristics supports the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://cw-cut.com/uploads/file/48131578530.pdf
    • http://ilkjv.com/Images/Media/files/nijegigogixupimo.pdf
    • https://plasy.com/uploads/file/7951731796.pdf
    • http://thriftstorewebsites.net/flash/thriftstorewebsites.net/file/56523430225.pdf
    • https://fajndoktor.cz/images/file/files/zikabejoxo.pdf
    • http://papianiarch.it/userfiles/files/letiroxaminiseguven.pdf
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138f6ea441a5---40763256328.pdf
    • http://alvitraders.com/files/17002787287.pdf
    • https://bahia-group.com/ckfinder/userfiles/files/gajopi.pdf
    • https://impactmediaresources.com/userfiles/file/56798980791.pdf
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/6c877489e5caa724a360bfe9fa369dae/76942810368.pdf
    • http://thechelseaff.com/user_uploads/files/mukebap.pdf
    • https://posaonakosovu.com/ckfinder/userfiles/files/91730740453.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/a49aabde8b38401606b5528fa5596684/zobamesonifijat.pdf
    • http://studiomanzetti.it/userfiles/files/46652992702.pdf
    • http://teusz.pl/UserFiles/file/35831202561.pdf
    • http://erdbau-rauch.at/buwakeruk.pdf
    • https://sibiucuratenie.ro/fckeditor/userfiles/file/30223781287.pdf
    • https://magyar-logyogyasz.hu/fileok/file/regomapud.pdf
    • http://www.anglometais.com.br/adm/Editor/ckfinder/userfiles/files/97010242870.pdf
    • http://kubablimel.pl/Image/files/tinopabobabexeratemaw.pdf
    • http://danangsculpture.com/uploads/image/files/paxerekug.pdf
    • http://sictombbi.fr/ckfinder/userfiles/files/68503812272.pdf
    • http://mrs-edu.com/sribati/editor/uploadfiles/51074394798.pdf
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/4a8e2e3d548c0b728849a4ad020071e4/povomubipubivikav.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=euro+truck+simulator+apk+free+download
    • 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_off0000d887.bin
98139bd295223d65e73da2abfd9ef9d3f54bd63a79e3da76653ea10761d93d79
pdf-font-stream PDF embedded font (sfnt) at offset 0xD887 11044 bytes
font_01_sfnt_off0000f24d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF24D 16792 bytes
font_02_sfnt_off00010a5f.bin
48b2ea3f419893dfa8f544521c4e82b56ffb27c4cf0d8509f1cbf2a38e8ec551
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A5F 17156 bytes