Malicious PDF — malware analysis report

Static analysis result for SHA-256 519848f9eba2c2ac…

MALICIOUS

PDF

74.4 KB Created: 2021-05-09 11:21:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1906f9ce82c7bb7eb73805ebf5501b52 SHA-1: c98ba824ac42f38f83e420b68b17031102bad8df SHA-256: 519848f9eba2c2ac431f858344d8d5612b37329a90475b4856898e63ae9df0b8
154 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, yafferge.ru, which is disguised as a search result. This indicates a phishing attempt to lure users to malicious infrastructure. The ML classifier and ClamAV detection strongly support the malicious nature of this PDF. No scripts were extracted, but the embedded URL is the primary indicator of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://yafferge.ru/strik?utm_term=what+does+a+flashing+green+light+mean+on+alexa
    • http://mnclassis.org/zaxobufamegemufomono22rf4.pdf
    • http://velixone.66ghz.com/ragexifevoguwiruxejaw.pdf
    • https://cdn-cms.f-static.net/uploads/4457590/normal_6054d1611026c.pdf
    • http://hookup154.fun/kingsman_the_secret_service_download_in_teluguhx3af.pdf
    • https://static.s123-cdn-static.com/uploads/4479705/normal_6007ffca6ca87.pdf
    • http://nudistoff.club/373291382212l7i9.pdf
    • https://static.s123-cdn-static.com/uploads/4417220/normal_6008ed5a3c2bd.pdf
    • https://cdn-cms.f-static.net/uploads/4381098/normal_60252e6d3180e.pdf
    • https://static.s123-cdn-static.com/uploads/4487416/normal_5ff96ba9bb98f.pdf
    • http://omynutural.space/69538340901bvoci.pdf
    • http://stepka2016.xyz/building_maintenance_excel_templatef70pt.pdf
    • https://cdn-cms.f-static.net/uploads/4462036/normal_601c60883d9b0.pdf
    • http://kushtanash.ru/indian_history_timeline_in_tamil4p3r8.pdf
    • http://streamsweets.com/tidomorixabuzogoberujijidgllxi.pdf
    • https://cdn-cms.f-static.net/uploads/4420610/normal_6028b1c16f220.pdf
    • http://vabuletarikinil.iblogger.org/vuwotebikipuxezuze.pdf
    • http://the-job.ru/ups_apc_back_550va_330whq6zu.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://gojanomoremage.rf.gd/bitetavo.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e6a5.bin
d126afa9fb137340c60cff5b958a77bf8d736fc17cd595a0006a2d8463f1b164
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6A5 5404 bytes
font_01_sfnt_off0000f8ee.bin
497765fc85910efb1406ff2f5e82a6f4573bedaa9e3a03c2cd911a8cea6d968c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8EE 10344 bytes