Malicious PDF — malware analysis report

Static analysis result for SHA-256 55df56d339beeec5…

MALICIOUS

PDF

81.0 KB Created: 2021-03-14 23:13:55 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 61b01356562fcb5aacdd5abc43256cc1 SHA-1: 15f0b80ea5c4fc04063a1aed850aa891c38c867e SHA-256: 55df56d339beeec5efd1b195959e0a3863dd9778da82ad419cd102a07591a233
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with one heuristic specifically identifying it as a 'PDF_SEO_LINK_FARM' containing 30 external links. The primary URL, https://nipisod.ru/strik, is likely part of a phishing or malware distribution campaign. While no scripts were explicitly extracted, the PDF structure and heuristic firings suggest an attempt to redirect users to malicious content, aligning with spearphishing tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://nipisod.ru/strik?utm_term=court+of+mist+and+fury+age+rating
    • http://rirelavemug.iblogger.org/motorcycle_keihin_carburetor_tuning.pdf
    • https://norofuzalugegok.weebly.com/uploads/1/3/4/8/134882219/vexomirupoxubus_parugokukitu_raset.pdf
    • https://wojaginobaxap.weebly.com/uploads/1/3/1/8/131857211/rudakoforiribogosel.pdf
    • http://xuxijosut.sportsontheweb.net/define_the_concept_of_programmed_decision.pdf
    • https://lukazerud.weebly.com/uploads/1/3/4/3/134343231/pofabewalubolab.pdf
    • https://sekikeke.weebly.com/uploads/1/3/4/7/134739811/5803567.pdf
    • https://cdn-cms.f-static.net/uploads/4464715/normal_600eb078b63df.pdf
    • https://cdn-cms.f-static.net/uploads/4478414/normal_6034278d08d23.pdf
    • https://static.s123-cdn-static.com/uploads/4390330/normal_5fdd90f795464.pdf
    • https://puduwuxibipufu.weebly.com/uploads/1/3/5/9/135966859/ee8b0c7fd8ada39.pdf
    • https://narusipanunajix.weebly.com/uploads/1/3/1/0/131069819/rikixu-juwububugusezi-nenufanat-gudorotuzof.pdf
    • https://cdn-cms.f-static.net/uploads/4450728/normal_60313457541b3.pdf
    • https://zijedizadof.weebly.com/uploads/1/3/4/6/134692085/8699455.pdf
    • https://static.s123-cdn-static.com/uploads/4407313/normal_5ff5941f3045d.pdf
    • https://buzapakamewogu.weebly.com/uploads/1/3/4/3/134366326/5753822.pdf
    • https://tezimapegimera.weebly.com/uploads/1/3/0/9/130968984/3e875.pdf
    • https://tipexuzujofetag.weebly.com/uploads/1/3/4/7/134718828/3582265.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.opentle.org
    • http://rufodax.rf.gd/julanulonodawepewoxekulut.pdf
    • http://xinifaduzinuvu.onlinewebshop.net/ryobi_2000_psi_electric_pressure_washer_price.pdf
    • http://rimejaje.epizy.com/64067424153.pdf
    • http://gidobiladuk.rf.gd/missed_abortion.pdf
    • http://saxodanokijaj.atwebpages.com/motorboat_merit_badge_worksheet.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
    • http://www.gnu.org/licenses/gpl.html

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ef29.bin
9adb6ffeb2ccb09c1bbd99ee8afd9174c2e479f4583614368bf73b50a8150f0c
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF29 5200 bytes
font_01_sfnt_off000100be.bin
d2d10b6b0c668cf26faa9347c7054f8580c7eefa5cb7aecda2a4fba74bd025f0
pdf-font-stream PDF embedded font (sfnt) at offset 0x100BE 6068 bytes
font_02_sfnt_off0001106f.bin
75bfe0a5e4909cbc927a8221b91022011149a8e653cab15aa35abdb48bef43ae
pdf-font-stream PDF embedded font (sfnt) at offset 0x1106F 11028 bytes