Malicious PDF — malware analysis report

Static analysis result for SHA-256 13a3a15adfb93fcb…

MALICIOUS

PDF

74.1 KB Created: 2021-06-27 19:46:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 683e6a003d9ba058389e2535fa1fd5c4 SHA-1: 0d8e7a0eb84f51ca4070272d5ac86a55e3d4927e SHA-256: 13a3a15adfb93fcb2df36c8d9ec5ee0103a9dfd4b6368547a26a3f104b49d751
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised WordPress sites, suggesting a link farm used to distribute malicious content or phish users. The PDF structure itself appears to be a link farm, leveraging compromised CMS uploads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cfbab973c6c---81530745066.pdf In PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2884986ce9---tazoxabopemi.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fe9c229cfb---romakezinorotog.pdfIn PDF document text
    • http://fobas.cz/userfiles/file/38141860310.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/7cce6e7ba7fc6378bccbfe5beed2894b/refulemebuwez.pdfIn PDF document text
    • https://kodcomputers.ro/2664/uploads/zoviw.pdfIn PDF document text
    • https://globalazeri.az/wp-content/plugins/super-forms/uploads/php/files/e7irajbpqvooaca8h2s4qvh4i2/piditajobijub.pdfIn PDF document text
    • http://hattingtoemrerogsnedker.dk/userfiles/file/rafilexozasa.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/6ad95495a8ee4248f028e52c1798c959/dezovo.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/241fcceeba7a47c6652568b0f7311187/gofitotavitesijesu.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606e781b401bf---35349073772.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/908jk4egr5toscrt5372c9fa4m/8231749985.pdfIn PDF document text
    • http://martonaroniskola.net/userfiles/file/83395849086.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/c548980f062f379f997e6bb4b0172798/76275099375.pdfIn PDF document text
    • https://www.vbclighting.com/wp-content/plugins/super-forms/uploads/php/files/4fdf6bc176089f2fe21318d32326561d/69594512692.pdfIn PDF document text
    • http://www.firengo.com/userfiles/files/zelunitowasitowasegulu.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607df6ed88ca6---tafel.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e09407ac76---83946090890.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/8nulcrmorkv36hnbpl674s79kf/59540632026.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/1609dfa9c476a5---70022387959.pdfIn PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607e97fb9e04f---vedosijubavurep.pdfIn PDF document text
    • https://canevastoilestjean.com/upload/editor/file/jukupawubaxoret.pdfIn PDF document text
    • https://jfefood.com/wp-content/plugins/super-forms/uploads/php/files/02bf61a4ad17fa54962cb36f01818d48/raboxijovefomifedodu.pdfIn PDF document text
    • http://aweibel.com/Photo/file/jezixaji.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c12ea79a6df---78745307886.pdfIn PDF document text
    • https://advantagelic.com/singhania/downloads/file/mitukebopitozivevunexuxak.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=tokyo+with+my+ghoulsPDF 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_off0000c22b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC22B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000da3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA3D 15932 bytes
SHA-256: 9f531cf80ef1df8345cbc207c71c6ae7ae938e324896bd3b31d9d1ed4504f920
font_02_sfnt_off00010367.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10367 10412 bytes
SHA-256: dd3b29ceafdf9d22fdead4c158db252d5ce20ad81ded06dd5b837ac5e02447e5