Malicious PDF — malware analysis report

Static analysis result for SHA-256 cba9d2e7c5638779…

MALICIOUS

PDF

74.9 KB Created: 2021-03-29 13:19:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: d7727c0843f3d5bfeca914d64607b8c0 SHA-1: 81d864ce096722c9cb5268eb16730850249335d9 SHA-256: cba9d2e7c5638779153bad94fa55c7d435bd7035fb904b5862a96b038ed925c2
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains a large number of external links, many hosted on disposable domains, suggesting it's part of a link farm designed to redirect users to malicious sites. The document body, though heavily obfuscated, contains keywords related to exercises and answers, likely a lure to attract clicks to the embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9843

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
  • 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.
  • 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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://midufefew.ru/award?keyword=indefinite+adjectives+exercises+with+answers+pdf PDF link annotation
    • https://cdn.sqhk.co/bitajububida/1gfgfhg/amazon_seller_central_login_uae.pdfIn PDF document text
    • https://cdn.sqhk.co/bugolajoxodu/f2ifgh1/buzzfeed_quizzes_guess_the_song.pdfIn PDF document text
    • https://jubaxotuxemis.weebly.com/uploads/1/3/5/3/135301284/7f2d05ee.pdfIn PDF document text
    • https://cdn.sqhk.co/puwipaneke/f53DgiW/pidowefumafajowoguxel.pdfIn PDF document text
    • https://tatabano.weebly.com/uploads/1/3/4/8/134850833/fekatizijikenag-vojibitoxut.pdfIn PDF document text
    • https://zewemoledomuro.weebly.com/uploads/1/3/4/7/134746436/zitali.pdfIn PDF document text
    • https://memabalizova.weebly.com/uploads/1/3/4/4/134490842/pumotok-fesevokewowawi-juxidulip-tesovidusimux.pdfIn PDF document text
    • http://jokojujut.medianewsonline.com/poverty_mindset_vs_abundance_mindset.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4388428/normal_600140562f15d.pdfIn PDF document text
    • https://pimelotug.weebly.com/uploads/1/3/4/5/134576353/tubizej-nisebiwitu.pdfIn PDF document text
    • http://gemubanabugawa.mypressonline.com/lapibi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409806/normal_6053166556c37.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4462374/normal_603ed56fa38be.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380223/normal_60248957586ab.pdfIn PDF document text
    • https://cdn.sqhk.co/jutafegobexe/WLCMRv6/75096723675.pdfIn PDF document text
    • http://valuburikodajad.medianewsonline.com/arabidopsis_book.pdfIn PDF document text
    • https://balesiloruj.weebly.com/uploads/1/3/4/6/134671801/8178089.pdfIn PDF document text
    • https://xarojitoma.weebly.com/uploads/1/3/5/3/135305856/kagoripojuduwo-dupofaj-lowewasot-lanet.pdfIn PDF document text
    • https://cdn.sqhk.co/mitebosareki/hNpgdhb/92676166946.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/takurugilij/jevupozobitoluwe.pdfIn PDF document text
    • https://s3.amazonaws.com/jefobexapulow/lidimukutukizegenejifuso.pdfIn PDF document text
    • https://s3.amazonaws.com/megulu/sccm_guidelines_icu_admission_discharge_triage.pdfIn PDF document text
    • http://xuvuzonixo.onlinewebshop.net/anne_of_green_gables_abridged_version.pdfIn PDF document text
    • https://s3.amazonaws.com/mefonevimimix/lavidotas.pdfIn PDF document text
    • https://s3.amazonaws.com/xakusineba/advantages_and_disadvantages_of_3d_internet.pdfIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f5aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5AA 5444 bytes
SHA-256: dbb4b32c46d184355e8959bb2d798ffe196c31fffeebf2cd98d7b7cd1ae8672f
font_01_sfnt_off0001084e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1084E 10500 bytes
SHA-256: 7b6e7dc3cd19c1646a1ee43735e93448191d5944375d63c45870c0ac91d2f5e8