Malicious PDF — malware analysis report

Static analysis result for SHA-256 87dcc17af7a658df…

MALICIOUS

PDF

81.3 KB Created: 2021-04-03 06:46:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b12ce3bf5b7067a4481246e3212530aa SHA-1: 247fd4e61e80533451ba61f8924e2de14620d150 SHA-256: 87dcc17af7a658df319a9a6d8ca97a0d1633c3714e400f320c873dea7c2717e6
156 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, indicative of a link farm or SEO spam campaign. The primary URL, https://xezojetit.ru/strik?utm_term=how+to+write+pseudocode+in+latex, suggests a lure to attract users interested in technical topics. ClamAV and ML classifiers also flagged this PDF as malicious, specifically as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://xezojetit.ru/strik?utm_term=how+to+write+pseudocode+in+latex
    • https://cdn-cms.f-static.net/uploads/4379485/normal_60307ee7cff70.pdf
    • https://static.s123-cdn-static.com/uploads/4403946/normal_5ff16952a98d4.pdf
    • https://naxozafo.weebly.com/uploads/1/3/1/4/131483391/solifofidiga_wunixebuwesak_zewoxoku_lejewowide.pdf
    • https://subusigigug.weebly.com/uploads/1/3/5/3/135316146/b8305f9b9c97831.pdf
    • https://wesuzekubiw.weebly.com/uploads/1/3/1/6/131607103/8820966.pdf
    • https://wixokaregojes.weebly.com/uploads/1/3/2/6/132681478/lazimebikebosapo.pdf
    • https://dugajivesunilo.weebly.com/uploads/1/3/4/8/134866737/geninitifipix_zezevofol.pdf
    • https://kofivenemiwelew.weebly.com/uploads/1/3/1/3/131380814/situzivu_moxabadi.pdf
    • https://static.s123-cdn-static.com/uploads/4421783/normal_5ff25a5c7ed4b.pdf
    • https://goremafijitem.weebly.com/uploads/1/3/4/6/134617837/pujuwaxig.pdf
    • https://cdn-cms.f-static.net/uploads/4451556/normal_60637b7cc50bf.pdf
    • https://waguwejulunesu.weebly.com/uploads/1/3/5/3/135301122/4539c4.pdf
    • https://cdn-cms.f-static.net/uploads/4469631/normal_604b1e234fe48.pdf
    • https://lidafeli.weebly.com/uploads/1/3/4/6/134683499/tejig.pdf
    • https://static.s123-cdn-static.com/uploads/4452377/normal_5fc5aef04f507.pdf
    • https://cdn-cms.f-static.net/uploads/4375342/normal_5fd7806792a1c.pdf
    • https://cdn-cms.f-static.net/uploads/4370068/normal_605d85e4078ae.pdf
    • https://static.s123-cdn-static.com/uploads/4527164/normal_5fff6d6c0ea6b.pdf
    • https://tizevilujiv.weebly.com/uploads/1/3/1/4/131406709/b30e3a948b2c1.pdf
    • https://tubuzitobez.weebly.com/uploads/1/3/4/1/134108618/1873621.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://s3.amazonaws.com/punagilelabon/mubebixivigugesofadim.pdf
    • https://s3.amazonaws.com/jimugivos/bully_lite_size_200mb.pdf
    • https://s3.amazonaws.com/lupuvogotog/vaveranebipisawekixiwuki.pdf
    • https://s3.amazonaws.com/muxozuvalubi/what_does_cash_allowance_mean_when_buying_a_new_car.pdf
    • https://s3.amazonaws.com/rirusozo/dorepuwakusunujinagasomo.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f010.bin
a3737fdc112f0e035d2ee866edd26d88499885c3eba40ede4bbfeef0f3cddf60
pdf-font-stream PDF embedded font (sfnt) at offset 0xF010 5072 bytes
font_01_sfnt_off00010167.bin
a18b025130e5566fe065985b5e0e81e256f0b3cc5555f57df340f84560a249f3
pdf-font-stream PDF embedded font (sfnt) at offset 0x10167 11824 bytes
font_02_sfnt_off000129d2.bin
4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3
pdf-font-stream PDF embedded font (sfnt) at offset 0x129D2 4324 bytes