Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6bca0634f9505fd…

MALICIOUS

PDF

82.9 KB Created: 2021-08-22 02:35:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 7fd4feef52d321972ef2e4b1e50b3519 SHA-1: a32bd61089b29b6785d4ce1dbbf79baead280140 SHA-256: a6bca0634f9505fdab6aab456299d2485f46ab5d51ea6e357e8c672e7d140dbc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. It contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting it functions as a link farm. The presence of a 'utm_term_redirector' and the nature of the URLs indicate an attempt to direct users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/vboffphpash9qa8u2rktid5q6i/56946398621.pdf In PDF document text
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1609d3239d80ba---jimulubekigeko.pdfIn PDF document text
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/df51v8pgsvou1e91ein6hs42pc/pefowibewimukajezefo.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/73icrgfr5lv786v2rel3rguuc7/gagobukozekoxized.pdfIn PDF document text
    • https://charqueadaboavista.com.br/wp-content/plugins/super-forms/uploads/php/files/4f77eb8edaf3640879b5063ad850c175/zijawelujevar.pdfIn PDF document text
    • http://sam-global.info/files/file/pevuvu.pdfIn PDF document text
    • https://abofahed.com/userfiles/file/seror.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/668a132f5d6f193474ec6ac24ccc22cd/zepuradoruxilekibivuj.pdfIn PDF document text
    • https://xn----7sbbjg7ctfs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f8eb98a469e35166577c05deb201b404/57399584467.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160a45e9a999fc---28557572715.pdfIn PDF document text
    • https://franchise-vietnam.com/app/webroot/img/files/wibus.pdfIn PDF document text
    • http://www.kigimex.com.vn/ckfinder/userfiles/files/kawejefavuliwibegutelewu.pdfIn PDF document text
    • http://huichem.com/ckfinder/userfiles/files/kixeradozivemeseb.pdfIn PDF document text
    • http://stadtbild-intervention.de/Quansis/ckfinder/userfiles/files/wasevekibev.pdfIn PDF document text
    • http://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b101269c70---dusiv.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/161218aa92519d---91715502358.pdfIn PDF document text
    • http://harasim.cz/uploaded/files/94405940001.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/5051671489.pdfIn PDF document text
    • https://mygoaltv.org/ipp/images/uploads/files/40813521669.pdfIn PDF document text
    • http://kimbuunguyen.com/uploads/userfiles/file/31820105678.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c03bc00bc82---10596373509.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5cd60c9e38---82185583256.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160ab1e61f330d---vamakaxagixuxasitodok.pdfIn PDF document text
    • http://abwcolley.com/uploads/files/79314366560.pdfIn PDF document text
    • https://techinnsrl.com/writable/public/userfiles/file/pimugavufirudirakenud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=download+valkyrie+connect+mod+apkPDF 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_off0000de76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE76 18308 bytes
SHA-256: b385ffd1537c261f7201986595d548f243cf68f3f1ecd05c64d000713500acce
font_01_sfnt_off00010d2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D2B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012542.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12542 10864 bytes
SHA-256: e5e1f3229cc3da24e6e5eb8211556b8e3a5298ef3c06afff52c18c67de6fae90