Malicious PDF — malware analysis report

Static analysis result for SHA-256 acc550c3d174531d…

MALICIOUS

PDF

77.4 KB Created: 2021-09-13 11:12:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1d87ebb58f3db62fa5eed5044c267dea SHA-1: e39ca279d82a2da247e01211d9e4c73203603e9b SHA-256: acc550c3d174531d646f2db6153072fe18a4a44d1535e680c18869b6c20113d7
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://pokewaveanaheim.com/uploads/files/tuwifebebofariz.pdf In PDF document text
    • http://levotst.com/uploads/files/51391948137.pdfIn PDF document text
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613cb0275b7f8---nusupovebasitoxu.pdfIn PDF document text
    • http://spielundlicht.de/content_provider/documents/files/geparupojavubab.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/161339254332ee---tokirilubo.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1613ec7b9b7c51---95078533899.pdfIn PDF document text
    • https://afmiletisim.afmiletisimajansi.info/resimler/files/niriwezi.pdfIn PDF document text
    • http://moneymaker-gold.de/files/zoneditan.pdfIn PDF document text
    • http://lnhaihui.com/userfiles/file/20210913142340_1739037110.pdfIn PDF document text
    • https://odlingfamily.com/userfiles/file/29671242195.pdfIn PDF document text
    • http://ad.ditroinfotech.com/laportal/ckeditor-ckfinder-integration/uploads/files/9315110581.pdfIn PDF document text
    • http://ibarugi.com/fckeditor/userfiles/file/belogamo.pdfIn PDF document text
    • https://gencshow.com/upload/ckfinder/files/nexasumuzejanu.pdfIn PDF document text
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/13022d6970f3f86d797291a7f3de7b14/17540469246.pdfIn PDF document text
    • http://daindnc.com/fckeditor/userfiles/file/fenuziwerivuf.pdfIn PDF document text
    • http://hangnhatbanonline.com/upload/files/walirenin.pdfIn PDF document text
    • http://anquocrealty.com/uploads/image/files/lejikera.pdfIn PDF document text
    • http://martonaroniskola.net/userfiles/file/73822578792.pdfIn PDF document text
    • http://honeycontacts.com/uploades/userfiles/file/vilutiruxev.pdfIn PDF document text
    • https://medicentrumnz.eu/medicentrum/files/file/13325079891.pdfIn PDF document text
    • http://barsugo.com/ckfinder/userfiles/files/50516962103.pdfIn PDF document text
    • http://livestreaming.group/wp-content/plugins/super-forms/uploads/php/files/hp3mb8vfiv5ikig112ibjh2aufud69q0/lojepabojanenulo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=minna+no+nihongo+1+kanji+pdfPDF 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_off0000c90b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC90B 10500 bytes
SHA-256: 0f5fede23419161fdce0f5fab570487e6101d6417c108db6c9f0a939e820df77
font_01_sfnt_off0000e09c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE09C 18476 bytes
SHA-256: 1d6a49f58eb3f494ca505f24c63a9337665face98e98e3a1e35cf9c2df4e0ce7
font_02_sfnt_off00011001.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11001 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1