Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c4c8f3c0a0b9568…

MALICIOUS

PDF

86.9 KB Created: 2021-09-07 23:51:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 20d4f975d52af24e19eb6220eeb44641 SHA-1: 4697d3dc084d974d0d1680924ea7c60543e4f402 SHA-256: 6c4c8f3c0a0b9568b8c9476d8f82d6c27a84a5f8b8a38176ff0ae4033b7ec83a
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious. It contains a link farm with numerous URLs pointing to various websites, many of which appear to be compromised CMS upload directories. The primary purpose seems to be SEO manipulation or redirecting users to potentially malicious content hosted on these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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
  • 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://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/4d0aaccf4eab9254e21676cd29e2a3e8/20867168544.pdf
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/74d1fc2ff0eca48a79d49eae28298be1/51453756172.pdf
    • https://topclassgreenery.nl/images/file/dujodarato.pdf
    • http://chapelguild.com/images/usr/kiwepinuluvozakizometofip.pdf
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/160b04ea178171---wupogi.pdf
    • http://olddieselparts.com/ckfinder/userfiles/files/filusenizekogolobisevo.pdf
    • http://rpsbchamber.org/editorData/file/xazarisewivozuditagafeb.pdf
    • http://michardardillier.com/ckfinder/userfiles/files/nidil.pdf
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/s14g7uhj6csjo4uu886ao55ho7/tezolubidozurusupiluta.pdf
    • http://sitepride.com/clients/c/c8/c8c605999f3d8352d7bb792cf3fdb25b/File/repozivaxuwagewara.pdf
    • http://chrisdepanneservices.fr/Sites/cds/files/jukebosozeju.pdf
    • http://chiangmai-esc.net/user_img/files/lukanopumiraj.pdf
    • https://alianzatours.com/imagenes/file/dovurijivubakufu.pdf
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b33a110ff8---wilirarajegopez.pdf
    • http://marta-galan.com/files/varios/file/47197395638.pdf
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160abf43237803---33472722177.pdf
    • https://footballsod.com/images/ck-uploads/files/45465655024.pdf
    • http://maidnheaven.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086e09a45b07---28596964056.pdf
    • http://cdn.eagle.mn/uploads/userfiles/files/16160125746.pdf
    • https://altinhediyeler.com/calisma2/files/uploads/zojesederiregiwet.pdf
    • https://rakowka.pl/userfiles/file/38581440087.pdf
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160813b94e83e6---17056171250.pdf
    • http://casaatlantida.com/userfiles/file///70703386063.pdf
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d3a1df649ee---dumitemusokulizepa.pdf
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/ee15d77286b5f835fea1aa94f310f8b6/36264194602.pdf
    • http://gonvvama.net/filespath/files/20210828235255.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=introduction+to+statistics+in+psychology+6th+edition+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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eab9.bin
69f5144f56a2e3752aa2f80e59424d0d52e1f3e0378e4fbe11f136dda93de6d4
pdf-font-stream PDF embedded font (sfnt) at offset 0xEAB9 18444 bytes
font_01_sfnt_off00011adf.bin
2baf35c5449b4cb903e1426782c14c38947897044193840fa5f8c8fca7d63af3
pdf-font-stream PDF embedded font (sfnt) at offset 0x11ADF 11232 bytes
font_02_sfnt_off000134fb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x134FB 16792 bytes