Malicious PDF — malware analysis report

Static analysis result for SHA-256 33b4ce7632be70b2…

MALICIOUS

PDF

81.1 KB Created: 2021-05-19 18:47:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 94c69f9d91484f0e559cb50db196d219 SHA-1: ab0633b0f213835768a61a9b9ea743ec86083ae3 SHA-256: 33b4ce7632be70b2e49c0166a62914f61dfd554924e76e83a12491173e54985c
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, with one heuristic specifically identifying it as a 'PDF_SEO_LINK_FARM'. One of the extracted URLs, 'https://zajinet.ru/strik?utm_term=how+to+prepare+for+ignou+bcom+a%2526f+exams', is flagged as potentially malicious. The ClamAV detection and ML classifier also indicate maliciousness, suggesting the document is designed to lead users to harmful content or exploit them. No scripts were extracted, but the presence of numerous external links points towards a phishing or SEO abuse attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://zajinet.ru/strik?utm_term=how+to+prepare+for+ignou+bcom+a%2526f+exams
    • https://cdn-cms.f-static.net/uploads/4447273/normal_6037983c495a3.pdf
    • https://zemizipip.weebly.com/uploads/1/3/4/0/134098502/rovefez_nelejazixase_bepikodedekepax_puludosol.pdf
    • https://static.s123-cdn-static.com/uploads/4417814/normal_5fe0e4ecb2b2a.pdf
    • https://ruwuzeget.weebly.com/uploads/1/3/4/7/134755445/dcdb71.pdf
    • https://pigogokeda.weebly.com/uploads/1/3/1/8/131857695/ec802308bf.pdf
    • https://cdn-cms.f-static.net/uploads/4480904/normal_602df98755a82.pdf
    • https://mogefitinovodug.weebly.com/uploads/1/3/0/9/130969954/gemekebadudoto.pdf
    • https://vonuvevija.weebly.com/uploads/1/3/1/4/131407152/betere-vepumubaf-dikijikufutu.pdf
    • https://biwawabagukolaz.weebly.com/uploads/1/3/4/7/134730268/6348452.pdf
    • https://visofebofoxofub.weebly.com/uploads/1/3/0/8/130814652/9907d6d8.pdf
    • https://cdn-cms.f-static.net/uploads/4450148/normal_60215f139ba16.pdf
    • https://tebojizo.weebly.com/uploads/1/3/1/4/131406069/tejokewomowukokenuze.pdf
    • https://torolanomopefi.weebly.com/uploads/1/3/0/7/130739669/nugesesedorogelewujo.pdf
    • https://peguduzivinaw.weebly.com/uploads/1/3/1/6/131606374/sopisovalogij.pdf
    • https://nogisapu.weebly.com/uploads/1/3/1/4/131453993/2841209.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/patotale/kumikerewudimuwasas.pdf
    • https://uploads.strikinglycdn.com/files/37f93de4-1f06-4f5e-94e2-5399f95191d8/how_to_setup_the_netgear_nighthawk.pdf
    • https://s3.amazonaws.com/moduluzuxikari/what_is_the_greysheet_food_plan.pdf
    • https://s3.amazonaws.com/davolazupivowi/gofojizelibigu.pdf
    • https://uploads.strikinglycdn.com/files/5d412014-0825-4196-8985-e863844a63bf/marathi_one_act_play_script.pdf
    • https://s3.amazonaws.com/zibenoroduzuw/82911934371.pdf
    • https://s3.amazonaws.com/rupatojuko/8200972823.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_off0000fe5e.bin
85a1302c94e532f49984f7949984952327a8878565fb2e5bc3411b022594bcdd
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE5E 5316 bytes
font_01_sfnt_off00011076.bin
0ecfc9f54b85aee983952a127dd1c7b49efa61f89a06130cd897bedb9e47a076
pdf-font-stream PDF embedded font (sfnt) at offset 0x11076 10916 bytes