Malicious PDF — malware analysis report

Static analysis result for SHA-256 2581b64e7dc3b0e4…

MALICIOUS

PDF

85.0 KB Created: 2021-09-17 20:21:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: e813371c772aa57468bfc6cb30478d12 SHA-1: b035c8d2bc7010353ecf2782f85f904fcd7ffed6 SHA-256: 2581b64e7dc3b0e46e21cf875dd802dfecb356e099babc5bbb3eb104bbbaa686
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as a link farm, with many embedded URLs pointing to potentially compromised or disposable hosting. The ML classifier and ClamAV also identified it as malicious, specifically as a phishing or trojan variant. The document body is heavily obfuscated and unreadable, suggesting it's designed to hide its true malicious intent, which is likely to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • 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://geodez.com/pliki/file/vigofonuwanugotigami.pdf In PDF document text
    • http://agriturismoilnoceto.com/userfiles/files/43953682943.pdfIn PDF document text
    • http://inbjnews.com/data/cheditor/0603/files/ruzivomufapulobuxa.pdfIn PDF document text
    • http://filipdegreef.be/uploads/files/71148371069.pdfIn PDF document text
    • https://aiwcecckolkata.org/FCKeditor/file/mowexize.pdfIn PDF document text
    • http://th-hl.com///upload/files/34537927314.pdfIn PDF document text
    • http://mya1fc.com/files/ckuploads/files/9175292834.pdfIn PDF document text
    • http://faisaltowel.com/survey/userfiles/files/19044782354.pdfIn PDF document text
    • http://marinapogon.pl/upload/file/106387412.pdfIn PDF document text
    • https://xn--dokumaanahtarlk-llc.net/userfiles/file/sakopefofesodisi.pdfIn PDF document text
    • https://belitour.ir/basefile/belitourir/files/6857311203.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/shf0e2b4g5m27i9nilh7avcg3o/riponupibigod.pdfIn PDF document text
    • https://sokolzgierz.pl/web/uploads/files/97162411015.pdfIn PDF document text
    • http://sinice-rasy.cz/files/file/modanajotop.pdfIn PDF document text
    • https://mystruggle.uk/indigo/ckfinder/userfiles/files/xamokamepaduwoxajoso.pdfIn PDF document text
    • http://tiszaikaland.hu/upload/file/ludaxo.pdfIn PDF document text
    • https://darkoyunpin.com/calisma2/files/uploads/16482149275.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/cb222d7911f0f7352e79f11a23e7b786/84634571054.pdfIn PDF document text
    • http://aftp.bg/userfiles/file/borafazigoxirudugurewi.pdfIn PDF document text
    • https://samngaimarble.com/html_upload/file/63514407588.pdfIn PDF document text
    • http://nadiadsa.org/userfiles/file/8234920781.pdfIn PDF document text
    • http://ux-school.ru/files/files/bipikopezeguru.pdfIn PDF document text
    • https://aljuboori.com/userfiles/files/70052362710.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614146a71cf2e---84258796314.pdfIn PDF document text
    • http://fkjz.cn/upload/files/2021/09/202109021121297860.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=music+player+that+works+with+android+autoPDF 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_off0000e53b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE53B 17908 bytes
SHA-256: bd06acb79cf324c4b43ac638dea65ccfb2a5beb7a5b028b7db4607792734a8a5
font_01_sfnt_off00011404.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11404 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012c1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C1B 10996 bytes
SHA-256: 43593d2f64f27a858b922f2345032f5f89b77e0357cbe9e85384cde69c7760ea