Malicious PDF — malware analysis report

Static analysis result for SHA-256 2ac25b2fc1243464…

MALICIOUS

PDF

97.4 KB Created: 2021-09-19 05:41:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5b5ae0ab9814d70e7b5c6af5cf0a6ec3 SHA-1: 923bf1acf952ffe97c7c75caf80a057fc305eafb SHA-256: 2ac25b2fc1243464a3c13b50ce0d6630cb29d999f470c5d7e25de75f483f97e4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, directing users to download files from compromised WordPress sites and disposable hosting, disguised as legitimate search results for free book downloads. The presence of numerous external URIs and link farm heuristics strongly suggests a malicious intent to distribute further malware or phishing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9888

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://crewmak.ru/uplcv?utm_term=passion+by+lauren+kate+pdf+free+download+english
    • http://smolninskayahotel.com/userfiles/file/vufuxafuju.pdf
    • http://yoshitomo-kokubunji.com/jcfiles/file/67222970593.pdf
    • https://confidence-ist.com/ckfinder/userfiles/files/40725589137.pdf
    • https://nonbodepsg.com/uploads/files/38492187161.pdf
    • http://citescolairedeledit.com/include/file/50410462732.pdf
    • http://kibbkw.com/uploads/file/lezorujapuronevoxobanaz.pdf
    • http://unite-chem.cn/upload/files/80192064226.pdf
    • http://ji-tien.com/userfiles/file/pexesilomoligipavip.pdf
    • https://bomnuocebara.com/quangbasanpham/app/webroot/upload/image/files/voxasima.pdf
    • http://manvilastrust-org.bvirani.com/ckfinder/userfiles/files/14163113529.pdf
    • http://life-worldwide.org/assets/uploads/files/wupuxaruguge.pdf
    • https://oceanflowerhotel.com/uploads/image/files/zuzuxoxezonizozi.pdf
    • http://scard.vn/app/webroot/uploads/files/konigopibogop.pdf
    • http://study4student.com/cache/fck_files/file/zevamaso.pdf
    • https://eghamatyab.com/basefile/bainbookcom/files/kelisavidapevusedajizekit.pdf
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/kgifkr95reo4fjtu00jbh6id8p/95016933607.pdf
    • http://farmaciacogliate.it/userfiles/files/47421832780.pdf
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133b77964cad---31263149320.pdf
    • http://sasolution.kr/userfiles/file/26265012869.pdf
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/ef1be5e7e79c21a7a142147a73e1b933/xarafipe.pdf
    • http://studiocommercialedelpiano.it/userfiles/files/toxanoxoradakupus.pdf
    • http://machulski.com/public/file/mefemogexosis.pdf
    • http://strandedtattoo.com/file/78991569986.pdf
    • http://mirai-kankyo.com/userfiles/files/pitudikikelow.pdf
    • http://tareeapartment.com/user_img/files/18462288636.pdf
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/1613ecee7b25ab---wurozogogemazide.pdf
    • 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_off000112a1.bin
622499db2dc181c2d3393de677f94804f9d451f39499e0e3328ed4334792ad70
pdf-font-stream PDF embedded font (sfnt) at offset 0x112A1 19288 bytes
font_01_sfnt_off000144d7.bin
4e0a1eaa2e18bbcb4079f209a03fcb8d4a5ca07fffd2690e229b35e8a8a501c1
pdf-font-stream PDF embedded font (sfnt) at offset 0x144D7 11312 bytes
font_02_sfnt_off00015f09.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15F09 16792 bytes