Malicious PDF — malware analysis report

Static analysis result for SHA-256 66864bc0ca692abc…

MALICIOUS

PDF

72.2 KB Created: 2021-09-27 09:56:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a1aa8d708f564c192253cbcccc1c5523 SHA-1: 5e4445639e7d793e4cda646c06f20d40b9708b0d SHA-256: 66864bc0ca692abc8a90be023d520f390ab441368eb6abcbb00d96eec9355e38
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many pointing to compromised CMS uploads or disposable hosting, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the numerous URLs serve as the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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 https://allytemp.ru/uplcv?utm_term=rise+of+the+tomb+raider+apk
    • http://rigosarchitects.gr/userfiles/file/sasiwaxe.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16133fd7bc2fc8---5194375597.pdf
    • http://888chji.com/userfiles/files/37776365221.pdf
    • http://childconnect.com/swi/fckfiles/file/vubewapesikaxefiduzij.pdf
    • http://annassteen.com/ckfinder/userfiles/files/64631988840.pdf
    • http://canshu.dlzj.net/upload/files/20210913214702547175.pdf
    • http://xn--9i1b14l32gg2dsybq3b.com/upload/fckeditor/file/gidajexes.pdf
    • http://www.johnrealestate.in/ckeditor-ckfinder-integration/uploads/files/58751831209.pdf
    • https://footballsod.com/images/ck-uploads/files/jivobomosekeruseb.pdf
    • http://kriosispl.com/cote_dor_import/admin/ckfinder/userfiles/files/57543478065.pdf
    • http://ambulatorioveterinariovianello.eu/userfiles/files/lajel.pdf
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613b928c68157---78485417243.pdf
    • https://liur-krd.ru/userfiles/file/85057763189.pdf
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/50232849536.pdf
    • https://highlander-inn.com/assets/userfiles/files/jadebiwazojipituzafuk.pdf
    • http://skrn.cz/pic/file/vovizurofujipiwewadirafuk.pdf
    • http://kehlux.lu/userfiles/files/45907343865.pdf
    • https://aspart.ro/ckfinder/userfiles/files/22520177254.pdf
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/161445d09ee96f---puwepifik.pdf
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613449a383f09---18967245074.pdf
    • https://posetili.ru/userfiles/file/61479559292.pdf
    • https://ximatinhdongnai.com/app/webroot/files/images/pages/files/suxejekokijomapubaj.pdf
    • 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_off0000b3af.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB3AF 16792 bytes
font_01_sfnt_off0000cbc6.bin
8638c2b1a8f32850539cf62da48eaefeb2fb5c9e8527e310732e8ac33f6afb04
pdf-font-stream PDF embedded font (sfnt) at offset 0xCBC6 10888 bytes
font_02_sfnt_off0000e4c2.bin
7c35657b3b4cc9dc6721bf5cb29b15f64af32b4d675625fab599edffe2d0f8dc
pdf-font-stream PDF embedded font (sfnt) at offset 0xE4C2 18636 bytes