Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3c877d51f514d57…

MALICIOUS

PDF

88.4 KB Created: 2021-06-30 11:35:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 05eacd2793c4b929f800db2bf6a358ec SHA-1: 9e090d2628c295ee2b2a26ccc57e9bba04c9a791 SHA-256: b3c877d51f514d57224dde43959372b1adcca8d59e4d30ee5681a8c253613f7f
156 Risk Score

Malware Insights

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

This PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and disposable hosting, likely to redirect users to malicious content or phishing pages. The presence of multiple external URIs and link farm characteristics strongly suggests a phishing or credential harvesting attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

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://oniceh.ru/uplcv?utm_term=falling+apart+at+the+seams+meaning PDF link annotation
    • https://soechi.id/userfiles/file/gevaxofuzezetenugowi.pdfIn PDF document text
    • https://seataclighting.com/wp-content/plugins/super-forms/uploads/php/files/92070c25b10d44d22e602730b3deb723/52134056465.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/160a9cf0974b43---digis.pdfIn PDF document text
    • http://colorfulmedia.de/fotki/fotki/file/81098571112.pdfIn PDF document text
    • https://mama-light.net/business_school/uploads/file/zawux.pdfIn PDF document text
    • http://firanywiktoria.pl/uploads/editor/file/51959128445.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/fupivujuno.pdfIn PDF document text
    • https://chief-moving.com/editor_upload/file/2230091935.pdfIn PDF document text
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/107a150ed9ee2d6fa7574b8e4d3c7cb8/lavujudejubezulefideso.pdfIn PDF document text
    • http://karunb.com/UpLoads/files/25038164962.pdfIn PDF document text
    • http://mesterek.net/tmp/naxipuxogafebinogugunese.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/80praro8a2pg4dfh0tkau5krss/memoguteku.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/160aa4df7e2ff8---52787642803.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/siruzefufopuwadolofami.pdfIn PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/1911e6e5728b478a9ffc058cbce53724/71029810203.pdfIn PDF document text
    • https://www.sacda.org/wp-content/plugins/super-forms/uploads/php/files/s0an88m6ojlblg6mqpk48l9mj7/77594402209.pdfIn PDF document text
    • http://csc010.com/userfiles/file/20210630132428_mwrhg7.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160847c0070cae---xatutunefe.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/cad664a52a9fb5d82c90f2dabf5d3f32/ruwotunowi.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160a347ee915a2---13052293342.pdfIn PDF document text
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/8b905dba1abcfd3d6918aa26f5615972/perovugomezukavel.pdfIn PDF document text
    • https://liniagdanskzydowo.pl/files/donewexupuj.pdfIn PDF document text
    • http://mp-hd.de/data/aktualnosci_imgs/file/belased.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/9324871ddc404074539a15f564fc85a4/seselom.pdfIn PDF document text
    • https://tims.ro/ckfinder/userfiles/files/lobivafizizewekubif.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be4d1c9c16d---dunivuzilij.pdfIn PDF document text
    • https://sonarmusic.hu/up_image/file/72005962270.pdfIn PDF document text
    • 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_off0000f17d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF17D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010994.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10994 10556 bytes
SHA-256: 54e8de3d95bc1c524bdad5c9e3e54736d97828a91d26a52a2c3f59dc8a351930
font_02_sfnt_off00012166.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12166 20332 bytes
SHA-256: 569f98d88b1c4a0a9a53c42bc1c372c9d9ae14fa1e42676ddf5c9f83c5d3090e