Malicious PDF — malware analysis report

Static analysis result for SHA-256 efdfd7ca68e4819e…

MALICIOUS

PDF

100.3 KB Created: 2021-03-15 07:29:18 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: bede7960d62f086779de9d3d2eadd73c SHA-1: cb5e8e9954078e46226ce3cbd47a087d6f1c5521 SHA-256: efdfd7ca68e4819eea9e59b9f623743070ea9fa7480224e91ed4143a648979be
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO manipulation tactic. While no scripts were explicitly extracted, the PDF structure and numerous external URLs point towards a phishing or malware distribution vector, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://bologen.ru/award?keyword=carnitina+pdf+2020 PDF link annotation
    • https://rebuxikaxaj.weebly.com/uploads/1/3/4/6/134668288/livuwapazirijob.pdfIn PDF document text
    • https://cdn.sqhk.co/pujazojiwixi/KNiqia2/94729697957.pdfIn PDF document text
    • http://xepuxupipe.mywebcommunity.org/dr_seuss_stories.pdfIn PDF document text
    • https://gidaletibom.weebly.com/uploads/1/3/4/8/134881461/teruzebaloposar.pdfIn PDF document text
    • https://cdn.sqhk.co/xubewarow/eiahNjj/24764152575.pdfIn PDF document text
    • https://cdn.sqhk.co/goluxewimabu/LgegiuS/33518128244.pdfIn PDF document text
    • https://cdn.sqhk.co/doxurozupu/jhAcib1/78067781238.pdfIn PDF document text
    • http://tejidirexe.mywebcommunity.org/vujuxeweginiguka.pdfIn PDF document text
    • http://gitikirazidapi.medianewsonline.com/how_to_reset_a_milwaukee_m18_battery.pdfIn PDF document text
    • https://vamawawu.weebly.com/uploads/1/3/0/8/130874524/jegaxujosuzupatereki.pdfIn PDF document text
    • https://cdn.sqhk.co/mitugejaxel/ijCWgcL/game_summoners_war.pdfIn PDF document text
    • http://gedatidigog.sportsontheweb.net/how_to_crochet_for_left_handers.pdfIn PDF document text
    • http://xafesuvorolivig.scienceontheweb.net/jakutagatetumop.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/c77f1be8-a3ab-424e-8418-b67b6dedcbed/thetford_toilet_seat.pdfIn PDF document text
    • https://065b66ee-25d8-4381-b309-094abc4d823c.filesusr.com/ugd/2703e6_2b6c652c045d4b15b00438cfebf60afa.pdf?index=trueIn PDF document text
    • https://667abc8f-92ca-45d9-bc9d-789c80a68858.filesusr.com/ugd/dcd78f_206a628b92c44bd4ac94350a26c3d437.pdf?index=trueIn PDF document text
    • https://8fc1c2d6-49ba-4d63-8b95-0327ef2b1627.filesusr.com/ugd/1849a1_6b5919a560944b1ea800635e38aaef17.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/de66c428-ff86-4e1b-a51a-c4dfe7961330/how_to_replace_battery_in_zagg_keyboard.pdfIn PDF document text
    • https://305aa2e3-e1d2-413d-aa2e-f1bb83d03ded.filesusr.com/ugd/92ee2b_48c7898a9ed94f22aac7632c2a858b3a.pdf?index=trueIn 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
    • https://doi.org/1In 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://scripts.sil.org/OFLIn 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_off000136b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136B0 5004 bytes
SHA-256: 7ccd34b66650422a7e875a08af9ec5ae90e07dfc14e84ff611c41f2230c97161
font_01_sfnt_off000147c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x147C6 10916 bytes
SHA-256: 28e99c12c8d0e377dac7f7e1ee0f626220139fb07eaa840dcd3f891cb28a3cc4
font_02_sfnt_off00016d37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16D37 16204 bytes
SHA-256: c988415812f594187b0a0ed75dc52802e798e1695b49bd300f8412a65040a449