Malicious PDF — malware analysis report

Static analysis result for SHA-256 fadd1b0f8c3b2aa6…

MALICIOUS

PDF

77.8 KB Created: 2021-09-13 02:37:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 781fd5bff7d6ef0ec0b55bf0d099e05d SHA-1: e51b26316bcdc1779ac83fb30b1959d0bdbdd586 SHA-256: fadd1b0f8c3b2aa6bf033a1d924978773203610da38638384ae632a356d7af10
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or are part of a link farm hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

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 https://archism.ru/uplcv?utm_term=super+mechs+friv PDF link annotation
    • https://mraos.com/web/userfiles/file/sovekudanuzum.pdfIn PDF document text
    • http://backupcenters.com/userfiles/file/61393653066.pdfIn PDF document text
    • http://midoriku.zaitakunet.jp/app/webroot/upload_images/files/tobilerebusigexan.pdfIn PDF document text
    • http://cuanhuaabshanquoc.vn/files/85725248550.pdfIn PDF document text
    • http://studiogaleazzo.eu/userfiles/files/momel.pdfIn PDF document text
    • https://e-tta.com/app/webroot/userfiles/files/14545588198.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613a75f8ab3c0---20317879218.pdfIn PDF document text
    • http://boschvietnam.com/files/usersfiles/files/bomivaji.pdfIn PDF document text
    • http://zoltysnieg.pl/pliki_wyswig/files/3985479259.pdfIn PDF document text
    • http://batterseataxi.com/survey/userfiles/files/86593761004.pdfIn PDF document text
    • http://elma-itc.ru/!upload/files/ratodogu.pdfIn PDF document text
    • http://drprdesaihospital.com/uploads/rofikujedorixuka.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136fc66a8ae9---robixividuvamupeg.pdfIn PDF document text
    • http://frutapacargentina.com/ckfinder/userfiles/files/29117594469.pdfIn PDF document text
    • https://isosklo.cz/uploads/pavufinixomodujim.pdfIn PDF document text
    • https://chungcungoaigiao.vnpec.xyz/uploads/files/kovafexisif.pdfIn PDF document text
    • http://tehnicgaz.eu/files/file/62347743587.pdfIn PDF document text
    • http://candientuvibra.com/images/file/legokuwoxaxabudujeregeb.pdfIn PDF document text
    • http://angelofthewinds.net/ckfinder/userfiles/files/kujigefalonefofo.pdfIn PDF document text
    • http://komodovo.ru/upload_picture/89126219079.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613176ac2ec68---fifajaginoroboneporaf.pdfIn PDF document text
    • http://decorstore.eu/upload/file/najutisevawudowojufujij.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_off0000c8ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8EC 10456 bytes
SHA-256: 96f0e3a9598768b70ffa06b16cb047f924744d0a1d778ee7209edd41a2781c5b
font_01_sfnt_off0000e0a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0A0 18812 bytes
SHA-256: c4b8f8e52763b5d0596b565981b011b907eb6901eeee5109d2a7c5b475c1cf17
font_02_sfnt_off000111df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111DF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1