Malicious PDF — malware analysis report

Static analysis result for SHA-256 4019b8d344000f7a…

MALICIOUS

PDF

83.6 KB Created: 2021-09-17 22:27:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b56636d4e886aec2bbf1b50f2dc848de SHA-1: d352ee159b475d7fec8c1b9a3c5a5b3fd6e24430 SHA-256: 4019b8d344000f7a393abf07f675c22876a780dee8da8ec6025ba904c5ba8e49
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file that contains embedded JavaScript, which is a common technique for executing malicious code. Several heuristics indicate the presence of external URIs, including one pointing to a raw IP address and others hosted on compromised WordPress sites, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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 http://tomei4x4.jp/js/upload/files/wumiwomunimoli.pdf
    • https://isosklo.cz/uploads/34178431734.pdf
    • http://garage-ys.info/js/upload/files/tugebom.pdf
    • http://12shio5.com/contents/files/rovenowujanurijawapide.pdf
    • https://rentcar888.com/uploads/files/202109031532224528.pdf
    • http://4998horo.gmmwireless.com/contents/files/48794954913.pdf
    • http://chaputlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jimagulidipixasakapok.pdf
    • http://kammerchor-lindau.com/file/romezefovurexutufimulok.pdf
    • http://spbmedax.ru/sites/default/files/uploads/81227677266.pdf
    • http://karinameal.com/imgdish/files/15693200660.pdf
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e8581645f3---niminifobojobesejulimiv.pdf
    • https://fallsplat.se/bildbank/file/4399785906.pdf
    • https://hohsingfiber.com/ufiles/files/vumoxulegaladijatevilusa.pdf
    • https://rafaellopezehijo.com/upload/files/bujum.pdf
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613bc4c04e54f---jumaxobomilazedejup.pdf
    • http://csptech.net/admin/userfiles/file/43942553075.pdf
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137d1eb08128---14063339808.pdf
    • http://charolais-hessen.de/write/userfiles/file/27748886527.pdf
    • http://xn--or3bi2da319p.com/upload/fckeditor/file/vizufugelisikajoxid.pdf
    • http://kartinatv.org/uploads/files/gekigo.pdf
    • http://140.121.125.49/ckfinder/userfiles/files/20210901_144728.pdf
    • http://sztarmedia.hu/_user/file/38191599182.pdf
    • http://aerotherminsulation.com/userfiles/file/72856841893.pdf
    • http://firewheels.pe/userfiles/file/zupudeb.pdf
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/161406c0a5d033---2192149916.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=doki+doki+literature+club+for+android
    • 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_off0000dc33.bin
e59f39225b27012753e87bfe6bb913147903dabd5ba93a5bcd6122448c421692
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC33 10632 bytes
font_01_sfnt_off0000f49b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF49B 16792 bytes
font_02_sfnt_off00010cad.bin
e30c76af0fc7954bfb7768f314d9117fae8c77f64fb34457a0f70d7fe187dc75
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CAD 20052 bytes