Malicious PDF — malware analysis report

Static analysis result for SHA-256 10822bd6fa54fd9a…

MALICIOUS

PDF

70.9 KB Created: 2021-10-02 22:33:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 253faa40575bff68848d52f0fb4ae70c SHA-1: 0083813d90ec17d6ca09a38a80821057937a85c9 SHA-256: 10822bd6fa54fd9a5edfe01f2f3c10eb7b24299318544918b8086dc53b8a382f
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://chcial.ru/uplcv?utm_term=noma+n1506+timer+instructions PDF link annotation
    • http://cyclad.org/UserFiles/file/4096954533.pdfIn PDF document text
    • http://urjabatteries.in/userfiles/file/gakokomakubo.pdfIn PDF document text
    • http://smart.sut.ac.th/tsme/src/lib/ckfinder/userfiles/files/fofipipuduweb.pdfIn PDF document text
    • https://kemxoi.vn/app/webroot/files/images/pages/files/pukuvunimanidetugiji.pdfIn PDF document text
    • http://www.sanjuktabanerjee.com/fckimages/file/45850889998.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/161532be055d3f---11384348159.pdfIn PDF document text
    • https://tekstilkentrehber.com/upload/ckfinder/files/77258827482.pdfIn PDF document text
    • https://3rproject.eu/ckfinder/userfiles/files/zukoxasewivofatuja.pdfIn PDF document text
    • http://aquamedia.cn/ckfinder/userfiles/files/kumufuposavisawifuxoz.pdfIn PDF document text
    • https://md-bud.pl/szklo/photos/file/xubipoxete.pdfIn PDF document text
    • http://krzysztofmalec.pl/gfx/fck/file/sipajopuxizumedabadi.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16158588c61b54---tukovasixuvujit.pdfIn PDF document text
    • http://2ds-creations.fr/userfiles/file/mopisexoga.pdfIn PDF document text
    • http://northmarking.com/userfiles/files/tobixetasopog.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/6mqq7ugioh6223ttmdq7j0ppnc/74626235663.pdfIn PDF document text
    • http://gildiamasterov.ru/userfiles/file/lomumuge.pdfIn PDF document text
    • http://bbbo.handyfriendship.com/upload/files/22519144465.pdfIn PDF document text
    • http://jocoseatee.com/userfiles/files/97379903894.pdfIn PDF document text
    • https://www.nhabe.com.vn/ckfinder/userfiles/files/40902373184.pdfIn PDF document text
    • http://bimbrlata.cz/UserFiles/File/nenapupirekamibuvi.pdfIn PDF document text
    • https://regenerateacademy.com/file/75537407910.pdfIn PDF document text
    • http://xn----7sbakif2a3azdub.xn--p1ai/admin/ckfinder/userfiles/files/89027367455.pdfIn PDF document text
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/161561503149f5---junigotudoje.pdfIn PDF document text
    • 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_off0000afcf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFCF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c7e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7E6 10900 bytes
SHA-256: c37331f528cf0f38e895ebe5504fe44e5592584f049f970cef9d8900b6a45979
font_02_sfnt_off0000e141.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE141 17488 bytes
SHA-256: 7fc8f052b704497811b1e0d264adf17bf17571f6d2c13243814bcdb04a4637bd