Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7c03b3543fd930c…

MALICIOUS

PDF

86.2 KB Created: 2021-07-06 13:34:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 10f8386eb5b339396d7df989979464f8 SHA-1: 50a24a4c865df1aa06f630f7befc8042193fdd25 SHA-256: b7c03b3543fd930c885f8602d66855983c8f5b00e436919773c131728a2daba4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript and a link farm pointing to compromised WordPress sites. The embedded JavaScript likely serves to facilitate the redirection or download of further malicious content. The numerous URLs, many hosted on compromised CMS platforms, suggest an attempt to obscure the final destination and evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/160baeb6df1ff8---23375204619.pdf In PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160908b4d5c294---gakomewegadumuraxa.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/7mi241eufn1uhl4g2pj46rofvl/lugadisujorivakejukazigu.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/43124bebc3b91a8b6f3b00c0e03f5ef7/revalulekawor.pdfIn PDF document text
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/bdnm557epaso55n3aih4v3faqs/45385603940.pdfIn PDF document text
    • http://cukierniabrzezinski.pl/www/artizam/fck/file/93015894338.pdfIn PDF document text
    • https://thetitangroup.ca/wp-content/plugins/super-forms/uploads/php/files/4c6f13807a575d77367221f0dabb1f7a/dululapinuwosamovoro.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/c410c834285b4b2bd6d1aa7b5bed85b3/mipipejok.pdfIn PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16078355292ad7---lodamukunijepalewozop.pdfIn PDF document text
    • https://mobile-translator.eu/app/webroot/media/files/wugepodikufimujo.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f7aa036af2---86045366495.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/0533bdab079a8da75b2b9fa7f54cf595/33015775079.pdfIn PDF document text
    • https://costabravas.com/uploads/localidades/files/bivexaguzumoborumedes.pdfIn PDF document text
    • https://strechybenesov.cz/content/57527122607.pdfIn PDF document text
    • https://teenvolunteer.org/wp-content/plugins/super-forms/uploads/php/files/9f3bcad1225026fbfb8158e449298378/32435746706.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085b2ba3fa8a---65502117056.pdfIn PDF document text
    • https://tasivn.com/upload/ck/files/veviri.pdfIn PDF document text
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/tduspd1mdd4sih5814qc17mkvm/54118731978.pdfIn PDF document text
    • https://rybczewice.pl/userfiles/file/77184613432.pdfIn PDF document text
    • https://bangprice.combangprice.com/beta/cms_image/file/xezukunepuxuxibabejo.pdfIn PDF document text
    • https://pensiuneavalentina.ro/app/webroot/file/goxezosofakedi.pdfIn PDF document text
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/160996c2419e3c---zabigoseveboko.pdfIn PDF document text
    • http://euhoca.com/js/ckfinder/userfiles/files/75543056686.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/34918850959.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/8r9lve15vp1h9i9he7j4c1tvn6/wuvarojujemimivumaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=omg+full+movie+download+480pPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC70 11160 bytes
SHA-256: d8452f18ed186cc1dbc549d4991325cbb26142d7c104b4a0bc9989ec19f9daa1
font_01_sfnt_off0001065b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1065B 17256 bytes
SHA-256: fca2301df8c09498746de272bd5caed6748009589df8c4755cebf7284205a701
font_02_sfnt_off0001336c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1336C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1