Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8fb4c1f7c425d8f…

MALICIOUS

PDF

71.4 KB Created: 2021-07-08 19:02:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ec2fda93f1713621543cc69c61d9d197 SHA-1: d863fc370100d16b3a5bf421cabb01859214dda4 SHA-256: b8fb4c1f7c425d8f4463b8cb9cd1fe22826b0e701f8bd2c6ccec86f313dd796c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://chcial.ru/uplcv?utm_term=gross+national+product+ppt
    • http://nceed.kr/pds/userfiles/files/jigisunujofelok.pdf
    • http://yonseri.org/userfiles/files/penigen.pdf
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/d64ca9b46c9ac1f3552d22ee8d59fc9c/wijufalufopatederatowimu.pdf
    • https://nnt52.ru/userfiles/file/lodoxaximarubulebuga.pdf
    • https://fid-data.fr/app/webroot/uploaderfiles/mamopogodarok.pdf
    • http://bsa.by/ckfinder/userfiles/files/10726877999.pdf
    • https://hosvagyok.hu/userfiles/file/laxewirilotazatovonur.pdf
    • http://jshtextile.com/UserFiles/file///rirusaxabaruxot.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078782fcfc02---dilusunuzek.pdf
    • https://nestaerospace.com/uploads/file/fevobuludixitulan.pdf
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c52e609fd8f---56847721452.pdf
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cf1d257e6e---nesafuz.pdf
    • https://papersacksfactory.ae/images/bulk_images/files/durarunisowa.pdf
    • http://soepcentrale-dekeyser.be/userfiles/file/rumokiluwefumatusa.pdf
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160782e69bc4b9---kixarotox.pdf
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/2c9952df554d95ee420ce1f1f0eea69c/xujilemuwadabuxije.pdf
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca5d2d8d05---19417664972.pdf
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160bc228e6535b---72633420681.pdf
    • http://igigeothermal.jp/userfiles/file/56443817425.pdf
    • https://www.northwoodmedical.ca/wp-content/plugins/super-forms/uploads/php/files/mtuj08hul12ik3lm2ci9m78hlq/40478766083.pdf
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160d491fa5a547---60771477075.pdf
    • https://honghow.com/ckfinder/userfiles/files/bepaxej.pdf
    • http://brooklynsmokeshops.com/admin/images/file/bewijufaxedaleb.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_off0000b58c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB58C 16792 bytes
font_01_sfnt_off0000cd9e.bin
35632d90740363177e3928d02df19caba586fdca02ef089eb2adb9693ad41936
pdf-font-stream PDF embedded font (sfnt) at offset 0xCD9E 16044 bytes
font_02_sfnt_off0000f721.bin
7136dcd0dad0cbf478572e34c71a2c2810f3519d2dc9d67c2dfbcd8f875ea4cf
pdf-font-stream PDF embedded font (sfnt) at offset 0xF721 10512 bytes