Malicious PDF — malware analysis report

Static analysis result for SHA-256 7761f1a941f06123…

MALICIOUS

PDF

97.2 KB Created: 2021-03-08 09:07:21 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-17
MD5: c713b21bba331802418c988769ac81ab SHA-1: dfbe1a234c23f9bc501b8bc633b589d349566d01 SHA-256: 7761f1a941f0612394fceadbb3eeb134c61fade2951aa70ad3e1217d3b61bc89
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URIs, indicating it functions as a link farm designed to redirect users to potentially malicious content. The document body is heavily obfuscated, but the presence of external links and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggest a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://golowaki.ru/strik?utm_term=yes+please+meaning PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4391642/normal_6007999285e2e.pdfIn PDF document text
    • http://requiredjokblog.com/63515407424i5dly.pdfIn PDF document text
    • http://neojust.ru/crazy_fruit_and_ice_cream_trujillo_instagramjvi02.pdfIn PDF document text
    • https://puzagetidorijes.weebly.com/uploads/1/3/4/4/134495880/d8fd13722cff02.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376612/normal_603ce0897509c.pdfIn PDF document text
    • http://good-production11.site/vubototudaru95ps.pdfIn PDF document text
    • http://dashcamtopbest.com/84238299566y0mpg.pdfIn PDF document text
    • https://cdn.sqhk.co/pubodegosog/hcUhht0/how_to_boost_your_children_s_self_esteem.pdfIn PDF document text
    • http://community-day.ru/fiwedo3rddq.pdfIn PDF document text
    • https://cdn.sqhk.co/lexijunibul/cbHhi6J/79469421955.pdfIn PDF document text
    • https://cdn.sqhk.co/ninubisidire/ZAHS1uI/bike_love_couple_wallpaper.pdfIn PDF document text
    • https://cdn.sqhk.co/dasisogi/DgecXhb/followership_leadership_epr_bullets.pdfIn PDF document text
    • https://sojanonef.weebly.com/uploads/1/3/0/9/130969598/zewibexidakenabowu.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4392658/normal_5fe2d0fbc1198.pdfIn PDF document text
    • https://zonotilikoper.weebly.com/uploads/1/3/1/0/131071062/3c4fe3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402956/normal_5feaf3c2e8fbe.pdfIn PDF document text
    • http://www.opentle.orgIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fedorahosted.org/lohitIn PDF document text
    • https://s3.amazonaws.com/pozokimepe/dumokomopufika.pdfIn PDF document text
    • https://s3.amazonaws.com/gujutavevive/benosadi.pdfIn PDF document text
    • https://s3.amazonaws.com/zunaporam/nugeno.pdfIn PDF document text
    • https://s3.amazonaws.com/goviwigax/crispr_cas_single_guide_rna.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://www.gnu.org/licenses/gpl.htmlIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 6

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_005_off00011b6a.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x11B6A 6048 bytes
SHA-256: 3c9eabe5ca2e283fea813745512e8de9875bfdb3b36d243cbb984922979cb4c2
font_00_sfnt_off0000e6ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6CE 7384 bytes
SHA-256: 0d1e95a1084b7c9ebee3aef7b48b3e20c23a86614b3d233201ec71c02e80fc62
font_01_sfnt_off0000ffc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFC2 5004 bytes
SHA-256: 1fad262cc80482836944bf0237d883fe49697ad83bdf23ae961bfae30f263182
font_02_sfnt_off000110bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110BC 2328 bytes
SHA-256: 864cbe2c6973b44d2b71e19ffbffb2328dcb3759b07ceb43c11d5a372fc4956d
font_04_sfnt_off00012adf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12ADF 17192 bytes
SHA-256: 8cd474d6d2248a8fe6f22fb14968b4a0b6bd5544dfe32bf501ca48af6d52cdf7
font_05_sfnt_off00015c22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15C22 17456 bytes
SHA-256: 5a53b3d9cadf8710ff38720f2190e7b48097d1bb6534ee96a3f74417c062814e