Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a4031b797b9c983…

MALICIOUS

PDF

76.2 KB Created: 2021-09-19 03:15:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 41bf5d16cca39dd0f00e2028dc076bb9 SHA-1: 18fa550246a9cf137e31dc03ecd85783dc9c43fe SHA-256: 3a4031b797b9c983ae69f3b35804a12fc50da258ae96c8d295269dc54b90c5f3
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a high number of external URIs pointing to link farms on disposable domains, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The embedded JavaScript likely facilitates the redirection to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9901

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://darslaska.org/ckfinder/userfiles/files/joleretatavusijuvozogajov.pdf In PDF document text
    • http://copy2d.com/ftp/image/file/13713809353.pdfIn PDF document text
    • http://robfredo.com/userfiles/file/4319087547.pdfIn PDF document text
    • http://thegrcinstitute.org/app/webroot/js/ckfinder/userfiles/files/9543936759.pdfIn PDF document text
    • http://jtipartner.com/ckfinder/userfiles/files/jobezipo.pdfIn PDF document text
    • http://abimobiliare.pl/pliki/File/25015718234.pdfIn PDF document text
    • http://impex-italia.it/userfiles/files/suxapezadefiwukejatep.pdfIn PDF document text
    • http://studiotecnicomaglio.it/userfiles/files/vepava.pdfIn PDF document text
    • http://reichspfarrer.sk/file/14186984288.pdfIn PDF document text
    • https://magnanelli.com/userfiles/file/33023280487.pdfIn PDF document text
    • https://luatkhangthai.vn/upload/fck/file/wegolosozenun.pdfIn PDF document text
    • http://7sate.com/filespath/files/20210908152531.pdfIn PDF document text
    • http://alhegazgroup.com/userfiles/file/fejidozezoritedegumax.pdfIn PDF document text
    • http://www.madiran-cruduparadis.fr/ckfinder/userfiles/files/duvexemalebabisigizumiw.pdfIn PDF document text
    • http://tjsijiqing.com/ckfinder/userfiles/files/2021/0912/4ea05c6d4c8d6f6e829c8f88f4e59cef.pdfIn PDF document text
    • https://angelsforwarriors.org/userfiles/files/fuzajufuv.pdfIn PDF document text
    • https://dawnraytech.985.tw/data/file/userfiles/files/jokuxixagaviz.pdfIn PDF document text
    • http://redemaisfarma.com/userfiles/file/kazudurun.pdfIn PDF document text
    • https://tigaintan.com/contents/files/dujiwafevasabe.pdfIn PDF document text
    • http://hoanggiaphatland.com/uploads/image/files/nuvonifupevonut.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161397a405a670---duvadapiginipujifu.pdfIn PDF document text
    • https://houstoncoinclub.org/FCKeditor/file/jasikawovifusivenipubirip.pdfIn PDF document text
    • https://samoinstitute.mn/uploads/assets/file/65526000500.pdfIn PDF document text
    • http://acsalma.hu/userfiles/files/48829598246.pdfIn PDF document text
    • http://arsvet.ru/img/upload/vuwababudagadulamameku.pdfIn PDF document text
    • https://ijpdua.com/contents/files/75725870151.pdfIn PDF document text
    • https://ozsersogutma.com/upload/files/3841294937.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=worlds+hardest+game+unblocked+2PDF 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_off0000c5ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5ED 16616 bytes
SHA-256: 089f56095a6d480f1cc040ad0f892bf9b05e3ae12c58e78c10c9f74120d0e7ee
font_01_sfnt_off0000f10d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF10D 11172 bytes
SHA-256: e04a00db1b72072fc02f12ff08f78a8f8f81344cfe53296ed848aa0a8cfe84bb
font_02_sfnt_off00010ae4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AE4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1