Malicious PDF — malware analysis report

Static analysis result for SHA-256 21baa6daabef7609…

MALICIOUS

PDF

89.9 KB Created: 2021-07-31 12:48:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5c0bfda8b87e79718ad08403dbfb5122 SHA-1: 141e92111666143f8d8574468df291a7840897c7 SHA-256: 21baa6daabef7609a008a86b4a7fce3a86cd75a2d3e97cfe6e30fc9c6d814be2
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to compromised WordPress sites and other disposable hosting, indicative of a link farm used for phishing or malware distribution. The ClamAV detection and ML classifier strongly suggest malicious intent, likely to lure users to malicious content or exploit kits.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

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://smidgel.ru/uplcv?utm_term=how+to+update+ms+word+2007+in+windows+10
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/6f757d83984d84715a6bc94ba6d9179a/tududegofemedozopurivo.pdf
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/1609e88583fbc1---68625530327.pdf
    • https://knurussian.kr/DATA/upload/files/202107051313576977.pdf
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/62il9c413m4lrbrj40ji7cr2b1/82695042081.pdf
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094cbc177a6e---motisijulabewane.pdf
    • http://sonarkella.com/userfiles/file/82966441812.pdf
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/16100b89adc024---65116220972.pdf
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/9p9fvhqim0a16sroho9pl6fufn/56548914805.pdf
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/03klnumt1ng32ghj753vst2nr6/98542597441.pdf
    • http://tokyoracing.hu/userfiles/file/39435529782.pdf
    • https://asthasupermarket.com/userfiles/file/75498747992.pdf
    • http://dermalab.pl/userfiles/file/sigoxepijolimu.pdf
    • http://hillcresthigh1971.com/clients/9/9f/9fbf9047a6869172a982db6f42f05a9a/File/buzanojigenivelatofoxif.pdf
    • http://architects-desk.com/uploadsfile/fozijodudokemotafibekit.pdf
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/cnmudlpe73ncj5f1m3rnbmjq1o/2968953191.pdf
    • http://vishwkarmaenterprises.com/webroot/img/userfiles/files/23396967494.pdf
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcaad2d7e55---15487256249.pdf
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160ad18618308c---24774871517.pdf
    • https://edoxmarketing.com/wp-content/plugins/super-forms/uploads/php/files/nq4n33vtvff6h0htg6vqct7mhl/73330624876.pdf
    • http://daedukgs.com/admin/fckeditor/data/file/20210710191404.pdf
    • https://khambenhxahoi115.com/images/files/napuwin.pdf
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/160927375c2af6---79205843817.pdf
    • https://www.zaantraining.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c77cbba825f---38831127880.pdf
    • http://agavietnam.com/img/files/fepijutane.pdf
    • https://devcons.org/uploads/userfiles/files/patapewalumi.pdf
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/158dbcb22ec84d4a3e3b5a3c233ac05d/60053827970.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_off0000f832.bin
8899ec9f6fe5e6d3e1ea8aceee692143176c1710e772de48c75a23188ba94d16
pdf-font-stream PDF embedded font (sfnt) at offset 0xF832 11028 bytes
font_01_sfnt_off00011200.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11200 16792 bytes
font_02_sfnt_off00012a12.bin
cdc76634f46add26936b33941db50bcb3fc3d00b55d75900f4396a32b83273f9
pdf-font-stream PDF embedded font (sfnt) at offset 0x12A12 17928 bytes