Malicious PDF — malware analysis report

Static analysis result for SHA-256 43a4f3c26ca9b9c1…

MALICIOUS

PDF

91.1 KB Created: 2021-07-27 01:16:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ae54a0d57b439236cc8f83590bffc0d6 SHA-1: b7e2834ffb0977e303bc9a4c59b82aa32fde7742 SHA-256: 43a4f3c26ca9b9c10b567a0b36c87723c5a9d2b8f5de5b6261b871998c1c1dcd
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document exhibits characteristics of a link farm, utilizing multiple distinct hosts, some of which appear to be compromised or disposable. The presence of a 'download button' heuristic further suggests a lure to download additional content. While no scripts were directly extracted, the ML classifier and ClamAV detection strongly indicate malicious intent, likely involving the distribution of further malware via the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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 http://yakutiaprime.ru/SITE/files/editor/file/gojutusawosamike.pdf In PDF document text
    • http://jadever.vn/Images_upload/files/45072961568.pdfIn PDF document text
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/1c981d60b88c2b303c2fa39dcb8209f8/27083188693.pdfIn PDF document text
    • https://pcstaiwan.com/ckfinder/userfiles/files/94275603162.pdfIn PDF document text
    • https://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/1607f62a8b3384---sanopikelumolelefora.pdfIn PDF document text
    • http://philboyd.com/lisubasezenejinodigurizi.pdfIn PDF document text
    • https://www.nitdgp.ac.in/uploads/userfiles/files/nojuzuwidibonamigapata.pdfIn PDF document text
    • http://ekopaczka.pl/imgbrama/files/73651377629.pdfIn PDF document text
    • https://aspirans.com/files/file/ximojenuzususegi.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/5d553348fa843f20922fae122c9fe4a9/sidewet.pdfIn PDF document text
    • https://sanipacific.com/attachment/file/pepakigapopirulapuwu.pdfIn PDF document text
    • http://seja.lv/assets/ckfinder/core/connector/php/uploads/files/juzuxamexitu.pdfIn PDF document text
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7366115211---6926744629.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/g08grivodjlnea005fdvs6scf4/53526036500.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8fe7f6e857---24312662040.pdfIn PDF document text
    • http://kasystemofkarate.com/clients/861259/File/fufatesomabodexozedafegu.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a4e01f02c3d---gowosanizokitakuwarezi.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/160817a25ac04b---nozuvonukazubemesuzelo.pdfIn PDF document text
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/653c4df538310c793f0fd6eae62feede/xewomijasotitirekiwegi.pdfIn PDF document text
    • http://jump360.co/upload/files/20210704022540.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab23f0de203---pogenofobezuzafebi.pdfIn PDF document text
    • http://ecandrychow.pl/Image/files/tunajatifojuvuxugipip.pdfIn PDF document text
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/372f974168fe1c6027be5a3adb97c976/tusoma.pdfIn PDF document text
    • https://sacc-la-chaux-de-fonds.ch/fichiers/file/jisidazusinesovazugogu.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/160970986de08b---wejom.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=how+long+to+use+easy+press+cricutPDF link annotation
    • 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_off0000ff35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF35 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011747.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11747 17200 bytes
SHA-256: ddbbacb80e4af08635dafda1db672eb4a14f0974d73c47e08108511acfe54a9e
font_02_sfnt_off00014430.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14430 10840 bytes
SHA-256: 863a3f4a49a8ff258cac37769d7129affbefba30c6848d597e23bc388f934685