Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ef35531b870cae4…

MALICIOUS

PDF

88.9 KB Created: 2021-08-02 22:55:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d33ff069037eba35ea0965f2a947db1b SHA-1: 5a69024dd503e6621d2d1f720758bbe190de3464 SHA-256: 4ef35531b870cae48a63f618ba6c80bc8cea2a00eb7da1ad9bd29d6ccc5148b3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. Several heuristics point to the document being a link farm, with numerous URLs pointing to compromised websites or disposable hosting, suggesting a phishing or malware distribution scheme. The presence of embedded URLs further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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 http://feuerwehrobrigheim.de/upload/files/rutegomuzabefitalojavenij.pdf
    • http://aci-immobilier-douai.fr/userfiles/files/jajalodejigofokojov.pdf
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d9f8a279241---kivulasikakolibutuzemek.pdf
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e398d401b0---70592702872.pdf
    • https://lea-inc.com/wp-content/plugins/super-forms/uploads/php/files/6b0e98c006747276fd3e6f04987a6229/44947546209.pdf
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080c109a00c7---degexamibukabawatoda.pdf
    • https://circolodelpistone.ch/userfiles/file/razigozedunovuvi.pdf
    • http://opalsolar.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160810eb7f2006---92224021305.pdf
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/boll51nbbg1pgukcpdbt9o5946/81936722273.pdf
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c85aadcff0a---davujam.pdf
    • http://suamayin.biz/userfiles/file/92767506578.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609eef51d6d4f---28589313399.pdf
    • http://luatsutiengtrung.com/app/webroot/uploads/files/lebid.pdf
    • https://szabobuszrendeles.hu/files/files/86444765401.pdf
    • https://leesman.com/wp-content/plugins/super-forms/uploads/php/files/ee5d0475d7599a0636067592e545bf3a/sirepapa.pdf
    • http://www.nagsa.es/ckfinder/userfiles/files/7710594663.pdf
    • http://aaaexpressac.com/userfiles/file/54645841552.pdf
    • https://boumqueur-edition.com/upload/fckeditor/file/lisesaba.pdf
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/76b9618df0a07fce9d68b400a9b02b89/zinopenaw.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/nsv46oica3ua3qj3egmdq06jk5/95892108892.pdf
    • https://nhatngudongkinh.com/upload/ckupload/files/8376329543.pdf
    • http://inphilong.com/upload/files/65565187638.pdf
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160dab34c45810---26512765276.pdf
    • http://thehonourride.ca/clients/c/c2/c2a221447f3e921143a55eca482c8289/File/75572891509.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=7.3+powerstroke+fuel+system+diagram
    • 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_off0000f720.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF720 16792 bytes
font_01_sfnt_off00010f37.bin
feaf13093f11fb37849798150efe6f47e9248b904612491144c9b887060fd4ce
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F37 11320 bytes
font_02_sfnt_off000129cc.bin
9719931ff401851a1c9e0bfb166f8c3c1b8a81022fccbbf6896d0b3c2282de60
pdf-font-stream PDF embedded font (sfnt) at offset 0x129CC 16652 bytes