Malicious PDF — malware analysis report

Static analysis result for SHA-256 cfb87b1ca4a8150a…

MALICIOUS

PDF

80.8 KB Created: 2021-09-24 03:27:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d1d66e11fa091fd42bae34fd1ce6a9ef SHA-1: aa0b3e6f805de73b0ab6946c4c8ee6fb1cc08076 SHA-256: cfb87b1ca4a8150a0599529b2663e401cba6aa3dd10e8eda1acbe053f246ddd4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external links, many hosted on compromised CMS platforms. These links likely serve as a link farm to direct users to malicious content or further download stages. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9933

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 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://pereplanirovkaoblast.ru/pict/file/58185291143.pdf
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/16138a3e8a52e1---16838144185.pdf
    • http://garage-fuji.jp/js/upload/files/lafuguzudusudetur.pdf
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/16132cc6a9813c---78269269030.pdf
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1614854854236a---vagemare.pdf
    • https://profesa.net/userFilesfile/bodaravanula.pdf
    • https://acrgruppe.de/userfiles/file/gegejawubovetite.pdf
    • http://ndc-group.ru/uploads/files/96908388961.pdf
    • https://parvazyab.com/basefile/api203/files/19461185887.pdf
    • http://brette-animation.com/userfiles/file/4438943827.pdf
    • http://pilot-market.ru/new/files/file/64069411077.pdf
    • http://richmore.kr/uploadfile/fckeditor/file/98550921162.pdf
    • http://labonscafe.com/userfiles/99928979947.pdf
    • https://khmernative-rice.com/userfiles/file/71370984494.pdf
    • http://xn----7sbakif2a3azdub.xn--p1ai/admin/ckfinder/userfiles/files/ravaropetepabutevenu.pdf
    • http://exim5.hu/_user/file/jipakusago.pdf
    • http://dwornawodzie.pl/userfiles/file/95412495790.pdf
    • http://dichvubaove.online/upload/files/52709480717.pdf
    • http://mikllc.mn/uploads/files/57674259648.pdf
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b50cd306e1---sopozixunopes.pdf
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c181613106---xikiboxuwovut.pdf
    • http://gerocuki.hu/user/file/tigob.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614595fe6ad33---72408052257.pdf
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1613ad57b2b602---safebiwowura.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=street+fighter+vs+tekken+apk+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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b6d4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB6D4 16792 bytes
font_01_sfnt_off0000cee5.bin
4f2409aa88bf6b583f4c224dcbf42814dd3cebad97f75ea1cff0e3a51ef31032
pdf-font-stream PDF embedded font (sfnt) at offset 0xCEE5 16380 bytes
font_02_sfnt_off0000e57b.bin
4588e260ce7d9456c547abba1e4c1920e6bd82704855ef6353c12790d39c5ca6
pdf-font-stream PDF embedded font (sfnt) at offset 0xE57B 21168 bytes
font_03_sfnt_off00011b46.bin
d433092deffd3b9daeea5adf6829f7f98265af444c4127edba8d76d5f8cfaffe
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B46 11096 bytes