Malicious PDF — malware analysis report

Static analysis result for SHA-256 6127d023868a0c4d…

MALICIOUS

PDF

91.5 KB Created: 2021-06-30 01:14:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8c3eb33eb70e9388af02eddf3c8eb357 SHA-1: b5d4d64571ae24b2d0a1dd5e565873a794da7b7c SHA-256: 6127d023868a0c4ded1c40d0ab7182deed635bee3dab363e9244d087d4b004a8
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It functions as a link farm, containing numerous URLs that point to external sites, some of which are hosted on compromised WordPress installations. The document body is heavily obfuscated and unreadable, suggesting an attempt to hide its true malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9941

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://auto-spec.ca/fck/file/rogemejigawilusot.pdf
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1607f96a91799b---87476244583.pdf
    • https://wavesmaroochydore.com/wp-content/plugins/super-forms/uploads/php/files/lhdkcali970t9pmlvr82rpnqs7/3621755908.pdf
    • https://inchiriereelicopterromania.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160ad0d66bab1b---fiduturumaso.pdf
    • http://aroma--style.net/files/files/11759952135.pdf
    • https://satybharat.com/ci/userfiles/files/gabopaxejijafutigokunex.pdf
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609421633fcdd---tuxubagupolagetakof.pdf
    • http://eraucheta.ru/uploads/file/34265739418.pdf
    • http://chingyi.tw/userfiles/files/rabosojupizimupafupunege.pdf
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7fa4ebe0b---35525612977.pdf
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/cf3cd8bdf9c271ff05698d372e8cf7a8/88404221283.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084ddbd87088---13761236979.pdf
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/96f0cebcaa91131bbe0aa2cf23a74efc/53604166806.pdf
    • http://bsa.by/ckfinder/userfiles/files/89322411006.pdf
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/1824406513.pdf
    • http://chinalanpa.com/images/upload/File/kemisudanexetebidowixu.pdf
    • https://ctapigroup3.com/contents//files/wuzen.pdf
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608e9fec45c4d---60432342984.pdf
    • http://ankurgroups.com/userfiles/file/musimaximoso.pdf
    • https://avigailpekelman.com/sites/default/files/file/13954940757.pdf
    • http://bearings-home.com/userfiles/file/lodufi.pdf
    • http://agro-vostok.ru/userfiles/file/mexujikilupefokod.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=death+march+to+the+parallel+world+rhapsody+s2
    • 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_off0000f72a.bin
b7d91dc8e0f7647e80d7c916bbef61797edfde97bef5096e3ac393b47b8e0f22
pdf-font-stream PDF embedded font (sfnt) at offset 0xF72A 1892 bytes
font_01_sfnt_off0000fffb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFFB 16792 bytes
font_02_sfnt_off00011812.bin
74bee80205a5478539b9924a73d239cfffc3d78ad92d1a55c6b98ac68ac24b91
pdf-font-stream PDF embedded font (sfnt) at offset 0x11812 10904 bytes
font_03_sfnt_off00013178.bin
e18252b0bf72361dbc68474c6dd65d9f08453e4b78c281b6c14ff39cfb96f274
pdf-font-stream PDF embedded font (sfnt) at offset 0x13178 17744 bytes