Malicious PDF — malware analysis report

Static analysis result for SHA-256 20ef99fd15a7c814…

MALICIOUS

PDF

80.8 KB Created: 2021-09-02 22:37:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2429c66a21cf5e13d7132d7d34ddff7f SHA-1: 41dfe9c880e30ade1c958c9c2ee762106c892c5c SHA-256: 20ef99fd15a7c81402ca0bf6d5ed065abb6faf39eff6aad1382d4cb540f69419
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It functions as a link farm, directing users to multiple external URLs, some of which are hosted on compromised WordPress sites. The presence of numerous links on disposable hosting further suggests malicious intent, likely to obscure the ultimate destination or to distribute malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://www.sherpachristain.org.np/ckfinder/userfiles/files/92745245275.pdf
    • http://starlightcelebre.com/clients/4/43/43e9139217482d7666ce300faf566241/File/duwilimajoge.pdf
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607f305e2df4f---21797813648.pdf
    • https://mut-zur-veraenderung-hambuch.de/userfiles/file/8913721743.pdf
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/6hdtpfuoohsku0bg25litn7tmi/sabetun.pdf
    • http://www.radeton-cz.vasestranky.cz/ckfinder/userfiles/files/5875988336.pdf
    • http://musicupclose.com/clients/f/f7/f7c291dfb329fbc33054893077acf627/File/72213009070.pdf
    • http://tauben-buchmeier.de/kleinberliner-schuetzen/userfiles/files/33580676490.pdf
    • https://burgaseguros.com/userfiles/file/nalepijefepag.pdf
    • http://daydreamspin.com/userfiles/file/faturawodot.pdf
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/bc05c11102535a96c3e0906f17dd9f5a/78676607107.pdf
    • https://vannordenvastgoed.nl/userfiles/file/tinapaxeri.pdf
    • https://universitecentrale.net/uploads/FCK_files/file/78297423859.pdf
    • http://samnakthodrahassob.com/userfiles/file/vamunaladomipigu.pdf
    • http://yasaitogo.com/uploads/files/ziwowaxijusodibezod.pdf
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16077862f7ae7c---nozuwagakugujitije.pdf
    • https://aljuboori.com/userfiles/files/sotozodabiwepunew.pdf
    • http://clubesquilacoma.com/uploads/files/muvadubizerata.pdf
    • https://bienenaktuell.com/sites/bienenaktuell.com/files/file/dasinapew.pdf
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160aa865b1f84f---jizunatikozekuzi.pdf
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/01b753de1188740293c9f34b89cb7ecd/mupijirubopuxa.pdf
    • http://keletunderground.hu/images/uploaded_pics/file/pateke.pdf
    • http://reklama-kemerovo.ru/files/files/wevav.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=foam+roller+exercise+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_off0000d70a.bin
552443631e903085c57e84b5366f612bcd631f0950d6a75ed4db01abc1fc8fcb
pdf-font-stream PDF embedded font (sfnt) at offset 0xD70A 17684 bytes
font_01_sfnt_off00010539.bin
e311943f534eeb50d8499bd9d68e5251ee9fe7c61b9deaba5281028a65c4bb63
pdf-font-stream PDF embedded font (sfnt) at offset 0x10539 10660 bytes
font_02_sfnt_off00011d9b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D9B 16792 bytes