Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c1b99293fe34416…

MALICIOUS

PDF

84.3 KB Created: 2021-09-20 19:12:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 1e8f58acfc80fcbdf0b94acb8906bea0 SHA-1: 57ab14a470c684e1754edcfe91040b2533de0b0a SHA-256: 8c1b99293fe344167524a83b8cca77f8e2d70e70542490b53b71da702d31f24f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically identified as a phishing trojan. Heuristics indicate the presence of a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. The embedded URLs likely serve as lures or downloaders for further stages of the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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
  • 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://chcial.ru/uplcv?utm_term=best+photo+design+app PDF link annotation
    • https://novsport.com/content/File/7952214992.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/b030537fe87966c27efb3e40e4a289d1/batokepalurazale.pdfIn PDF document text
    • http://belovosushi.ru/files/78966803185.pdfIn PDF document text
    • http://manpukuorder.com/uploads/files/lerojusatu.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/scp5o7m5jo28caqffq1cohv29q/21521536386.pdfIn PDF document text
    • https://verredistri.fr/xmedia/file/gobavafag.pdfIn PDF document text
    • https://mimpishio2.com/contents/files/sezig.pdfIn PDF document text
    • https://momsgardenfoods.com/ckfinder/userfiles/files/famatulovusinabupan.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/900abed2eb40bfd5715b3634801a661f/wetamodimepuxejeliraso.pdfIn PDF document text
    • http://huabulaw.com/uploadpic/2021-9/file/2021091406453673499.pdfIn PDF document text
    • http://poketomecam.com/uploads/files/54603221464.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/161404f2375c42---sixexemo.pdfIn PDF document text
    • http://indecomavo.pl/userimg/inc/19711364374.pdfIn PDF document text
    • http://bodybybodyology.com/ckfinder/userfiles/files/xekesegusaw.pdfIn PDF document text
    • http://udaybharat.in/ckfinder/userfiles/files/71897560262.pdfIn PDF document text
    • https://shunnasato.com/waloduvej.pdfIn PDF document text
    • https://motecx.com/images/file/tipunevipusetabuzalelo.pdfIn PDF document text
    • http://apexnepaltravel.com/userfiles/file/momajapimudulopejavut.pdfIn PDF document text
    • https://pracowniatechart.pl/fckpliki/file/83334447103.pdfIn PDF document text
    • http://miet-boot.ch/images/uploadedimages/file/zegemodovoliwizoziwawax.pdfIn PDF document text
    • http://ymmicro.com/files/files/92592389149.pdfIn PDF document text
    • http://masan315.net/board/imagefile/file/87777627812.pdfIn PDF document text
    • http://speednewslive24.com/assets/ckfinder/core/connector/php/uploads/files/80267891846.pdfIn PDF document text
    • http://xn--lv0az70cxar.tw/uploads/files/202109070209196436.pdfIn PDF document text
    • https://pilot-nav.socksnbows.com/ckfinder/userfiles/files/fidupev.pdfIn PDF document text
    • http://xn--80aadcnaeutgftohcogh8i8dsc.xn--p1ai/pict/file/52117410489.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e5e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5E6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fdf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDF8 17624 bytes
SHA-256: 97d86e3d8ae6385171017ffa8cb49f01af92a7fa31a8645bf1f80d7c7699b0b5
font_02_sfnt_off00012b60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B60 10580 bytes
SHA-256: f6a1730f7eebb6b3a2e92fb8432da50502fec259549efc9157383fa44350714a