Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdc36788948a13fb…

MALICIOUS

PDF

85.3 KB Created: 2021-07-05 06:08:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 12049977fb2223a2df9b9f94389201a7 SHA-1: 42698f49907e856d68dd9471cf2a517c8b0ccded SHA-256: cdc36788948a13fbe732a79a09943f05fda91ac10dab8cedee48782b183155f1
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with many URLs pointing to compromised CMS upload storage or disposable hosting, suggesting a phishing or malware distribution scheme. No scripts were extracted, and the document body was unreadable, limiting further analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://girisimcilikproje.com/resimler/files/85061921145.pdf In PDF document text
    • http://kfbi.ru/content/file/kimunepu.pdfIn PDF document text
    • https://mollis.rs//files/77275055365.pdfIn PDF document text
    • https://socohoteldanang.com/uploads/image/files/lexufe.pdfIn PDF document text
    • https://hoalavender.net/upload/files/68690106232.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073d4d002d54---22797419733.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/b63801aca0fa409efea944b732600ea4/18834589613.pdfIn PDF document text
    • http://a-swiss.com/upload/userfiles/file/nekusesawevuda.pdfIn PDF document text
    • https://ppuhperspektywa.pl/files/edytor/file/mezepera.pdfIn PDF document text
    • http://a1-automotivegroup.com/upload/files/rerovasivilikifiwapagi.pdfIn PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3e81730f3c---gugamisudavimisekevim.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608d03959e216---81553997641.pdfIn PDF document text
    • http://piau-po21inn.com/CKEdit/upload/files/vetagiduwez.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/2f5a9acfe49aae37c80ba4838c01b0de/65659055077.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/gonivupikafedesulonesuz.pdfIn PDF document text
    • https://communeouchamps.fr/userfiles/file/tojalifupamu.pdfIn PDF document text
    • http://mnogonomerov.ru/uploads/file/ziwozazeralatibuk.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160a736ef3f481---46832486290.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16087ee932639a---neluvasozifiradikonina.pdfIn PDF document text
    • http://schodylux.pl/userfiles/file/debowelizigaworulileva.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/76088617c81fa2d7628507342b2408dd/40235201557.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/37632586507.pdfIn PDF document text
    • http://tsradviseurs.nl/mailing/images/photo/file/91342556365.pdfIn PDF document text
    • http://prosquash.by/data/22026839352.pdfIn PDF document text
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/gg5inh0fdalogk1o9oa22pudf1/lusadixawonomoz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=third+law+of+thermodynamics+examplesPDF 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_off0000e629.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE629 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fe40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE40 11148 bytes
SHA-256: c68ace9b629b4daf7917009430c9573ffa399d1245a63ec65d6024e4a94e521b
font_02_sfnt_off00011831.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11831 17644 bytes
SHA-256: fdad47cc1be25a2dcb1a9e9c16d5888ad13739c370ce0347207eb873a6d1929f