Malicious PDF — malware analysis report

Static analysis result for SHA-256 4dbbc4e52272c148…

MALICIOUS

PDF

83.1 KB Created: 2021-04-10 16:41:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 7184da8a7592884ea0b32f930a212bbf SHA-1: 2579b84240e1f8b88ed48f6d41f81208dd02fe12 SHA-256: 4dbbc4e52272c148652c54d716674176eca871a93c797e2c3a184d77aa72acaa
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including ClamAV and an ML classifier, as malicious. It contains a large number of external links, many pointing to benign-looking PDFs, suggesting a link farm or SEO spamming operation. One of the primary external links, 'https://seumenha.ru/strik?utm_term=heil+hvac+heat+pump+reviews', is likely the intended destination for users, disguised as product reviews.

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://seumenha.ru/strik?utm_term=heil+hvac+heat+pump+reviews
    • http://vazagitomis.mypressonline.com/audiometria_interpretao.pdf
    • http://pagavopalubutu.scienceontheweb.net/tabux.pdf
    • https://cdn-cms.f-static.net/uploads/4425506/normal_605f797d825ef.pdf
    • http://zelumefepa.sportsontheweb.net/givavupugidok.pdf
    • https://cdn-cms.f-static.net/uploads/4369760/normal_60490d00903f7.pdf
    • http://moradudipomibo.mypressonline.com/amsterdam_transport_map.pdf
    • http://xutusurekawidi.medianewsonline.com/57334863403.pdf
    • https://cdn-cms.f-static.net/uploads/4387417/normal_604bbe5a8daa3.pdf
    • http://wabiferofuvud.mygamesonline.org/fashion_design_company_profile.pdf
    • http://zonitupupafof.sportsontheweb.net/flowers_in_the_attic_series_in_order_lifetime.pdf
    • https://cdn-cms.f-static.net/uploads/4501774/normal_602dce42aeb0d.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://204833c8-abda-4421-8777-5048ee7dd919.filesusr.com/ugd/e30b7a_dbb9a84623f8433c92d048aa94d42ecf.pdf?index=true
    • https://s3.amazonaws.com/pazatuv/26661141749.pdf
    • https://s3.amazonaws.com/wovedukevikov/dunogajigipu.pdf
    • https://s3.amazonaws.com/zubuwujoxom/dijuvafagogobelus.pdf
    • https://39c10a3a-92c6-412a-a1bb-b8a1fc48fbc4.filesusr.com/ugd/259099_a608ab5005a34f1192e3b22b3420e663.pdf?index=true
    • https://44bb6ee8-a0fe-4f72-890f-0f0a2fec05cf.filesusr.com/ugd/b65acf_09d36628651b469d9f7ba1cf4dfd0709.pdf?index=true
    • https://s3.amazonaws.com/towakog/jixizagukupukebijopesado.pdf
    • https://s3.amazonaws.com/litunux/kasazogal.pdf
    • https://s3.amazonaws.com/ponivotigegepub/ejemplo_de_dialogo_investigacion.pdf
    • http://wovodijulenape.onlinewebshop.net/8265532179.pdf
    • https://s3.amazonaws.com/bomupi/decimator_md_hx_user_guide.pdf
    • https://s3.amazonaws.com/vutame/37444053891.pdf
    • https://94aa8f26-b07a-4c24-bdb4-4112657565c9.filesusr.com/ugd/37428b_d8779f51f7cf4f2390189adce083639b.pdf?index=true
    • 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_off0000fa44.bin
ecf0d75407da9a3a21e97376fd99be3302da73db4f8b1d815cfff2dc8f148d72
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA44 4952 bytes
font_01_sfnt_off00010b24.bin
d05715e7174e7706ac9866d2bc5094282bbfcf9cf4c23359849b389f1347b1be
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B24 11372 bytes
font_02_sfnt_off000130fe.bin
a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f
pdf-font-stream PDF embedded font (sfnt) at offset 0x130FE 4324 bytes